Explanation: When troubleshooting network connectivity issues on OS X Yosemite, one of the first steps to take is to reboot the computer. Rebooting can help reset network configurations and resolve temporary network issues. While the other options may be relevant in certain situations, rebooting is often the quickest and most effective troubleshooting step for network connectivity problems.

Explanation: Slow performance on an OS X Yosemite computer can be caused by various factors, but one common troubleshooting step is to clear the cache files. Cache files can accumulate over time and affect system performance. By clearing these files, Mr. Johnson can free up disk space and potentially improve the overall performance of his computer. While the other options may also be relevant in certain scenarios, clearing the cache files is a good initial step for addressing slow performance.

Explanation:
The correct answer is (c) Reset the SMC (System Management Controller). When troubleshooting a slow startup issue on a Mac, resetting the SMC can help resolve various power and hardware related problems. This process involves shutting down the Mac, disconnecting the power adapter, removing the battery (if removable), and then holding down the power button for at least 10 seconds. After that, the user can reconnect the power adapter (or reinstall the battery), and start the Mac again.

Explanation:
The correct answer is (d) Forget and rejoin the Wi-Fi network. When a Mac is unable to connect to a Wi-Fi network, forgetting the network and then rejoining it can help resolve the issue. This can be done by going to the Wi-Fi settings, selecting the network in question, and clicking on the “Forget” option. After that, the user can select the network again and enter the necessary credentials to reconnect.

The correct answer is (d) Create a new user account and test the applications. When troubleshooting frequent application crashes, creating a new user account can help determine if the issue is specific to the user’s account or system-wide. By creating a new user account and testing the applications in that account, the user can identify if the crashes are related to their account settings or if it’s a system-wide issue. If the applications work fine in the new user account, then the issue is likely with the user’s account settings.

Explanation:
Verifying disk permissions can help identify and resolve issues related to the file permissions on a Mac. When application crashes occur frequently, it could indicate a problem with the permissions of specific files or folders required by those applications. Verifying disk permissions ensures that the necessary permissions are correctly set, which can help resolve application crashes and improve system stability.

Explanation:
When an application becomes non-responsive, force quitting it and relaunching can often resolve the issue. Force quitting terminates the application and allows Mr. Thompson to start it again from scratch, potentially resolving any temporary glitches or conflicts that were causing it to become unresponsive. Restarting the computer or resetting PRAM/NVRAM are more general troubleshooting steps and may not directly address the non-responsive application issue.

Explanation:
Console.app is a built-in troubleshooting tool in OS X Yosemite that allows users to view system logs and diagnose issues, including system crashes and panics. It provides detailed information about the events leading up to the crash, which can help identify the cause of the problem. By analyzing the logs in Console.app, technicians can pinpoint the source of the crash and take appropriate troubleshooting steps.

Explanation:
Slow performance on a Mac can often be attributed to insufficient memory (RAM). By upgrading the RAM, Mr. Johnson can improve the overall performance of his Mac. This is especially true if he frequently runs memory-intensive applications or has multiple applications open simultaneously. Upgrading the RAM will provide more memory for the system to work with, reducing the need for frequent disk swapping and improving overall responsiveness.

Explanation:
Disk Utility is a built-in utility in OS X Yosemite that allows users to manage and troubleshoot disks and file systems. It provides a graphical interface to verify and repair file system errors on a Mac’s startup disk. By running the First Aid feature in Disk Utility, users can scan the disk for errors and repair them if necessary. This can help resolve issues related to file system corruption and improve the overall stability and performance of the Mac.

Explanation: The correct answer is C) Run hardware diagnostics. Kernel panics are often caused by hardware issues. By running hardware diagnostics, you can identify any faulty components and take appropriate action. Resetting the NVRAM/PRAM (option A) can help in some cases, but it is not the first step in troubleshooting kernel panics. Reinstalling the operating system (option B) and updating third-party software (option D) are unlikely to resolve hardware-related kernel panics.

The correct answer is D) Fragmentation can occur on Macs, especially on traditional hard drives. While Macs have a more efficient file system compared to Windows, fragmentation can still occur, especially on traditional hard drives. Macs do not automatically defragment files in the background (option B), but they do have built-in mechanisms to optimize file storage. However, over time, fragmentation can still impact performance, particularly on hard drives.

Explanation: The correct answer is (c) Library folder. In OS X Yosemite 10.10, the startup items are stored in the Library folder at the root level of the startup disk. To manage startup items, you can navigate to the Library folder and look for items in the following locations: /Library/StartupItems, /Library/LaunchAgents, and /Library/LaunchDaemons. By removing or disabling unnecessary startup items, you can improve the performance of the Mac.

Explanation: The correct answer is (b) Reset the network settings on the Mac. Resetting the network settings can often resolve connectivity issues with Wi-Fi networks. To reset the network settings on a Mac running OS X Yosemite 10.10, Mr. Johnson should go to System Preferences > Network, select the Wi-Fi connection, and click on the “Advanced” button. From there, he can choose the “Reset” option to reset the network settings. This will remove any saved Wi-Fi networks and their associated preferences, allowing Mr. Johnson to start fresh and attempt to connect to the Wi-Fi network again.

Explanation: The correct answer is (a) Faulty hardware. Kernel panics, which are unexpected system crashes, are often caused by hardware issues. It is possible that the Mac has a faulty component, such as a failing RAM module or a malfunctioning graphics card. To troubleshoot this issue, you can start by running hardware diagnostics on the Mac. Restart the Mac and hold down the “D” key during startup to access the built-in Apple Hardware Test. If any hardware issues are detected, you may need to replace the faulty component to resolve the kernel panics.

Explanation:
The correct answer is (a) ifconfig. The ifconfig command is used to configure and display the status of network interfaces on OS X Yosemite. It provides information about IP addresses, network masks, and other network-related settings for each interface.

The other options are incorrect:

(b) ping is used to test network connectivity by sending ICMP echo request packets to a specific destination.
(c) netstat is used to display network connection information, routing tables, and network interface statistics.
(d) traceroute is used to trace the route that packets take from the source to the destination, displaying the IP addresses of the routers along the way.

Explanation:
The correct answer is (c) diskutil. The diskutil command in OS X Yosemite is used to manage disks, partitions, and file system-related tasks. To repair file system permissions, the command “diskutil repairPermissions /” can be used. This command repairs the permissions on the root (“/”) directory and its subdirectories.

The other options are incorrect:

(a) chmod is used to change the permissions of files and directories.
(b) fsck is used to check and repair file system consistency.
(d) repair_permissions is not a valid command in OS X Yosemite.

Explanation:
When a Mac is not booting up, resetting the SMC can often resolve the issue. The SMC is responsible for managing various hardware functions on the Mac, including power management. By resetting the SMC, it can help fix issues related to power management and potentially resolve the booting problem.

To reset the SMC, Mr. Johnson can follow these steps:

Shut down the Mac.
Unplug the power cord.
Wait for 15 seconds.
Plug the power cord back in.
Wait for 5 seconds.
Turn on the Mac.

Resetting the PRAM (Option b) is not the correct answer in this case, as it primarily deals with storing certain settings such as volume, screen resolution, and startup disk selection. Reinstalling the operating system (Option c) may be necessary in some cases, but it is not the initial troubleshooting step. Replacing the hard drive (Option d) is not recommended unless there is a clear indication of a hardware failure.

Explanation:
Slow internet connectivity can often be resolved by restarting the modem and router. This helps in refreshing the network connection and resolving any temporary issues.

To restart the modem and router, the user can follow these steps:

Power off the modem and router by unplugging them from the power source.
Wait for 30 seconds.
Plug in the modem first and wait for all the lights to stabilize.
Then, plug in the router and wait for the lights to stabilize.
Test the internet connectivity on the Mac.

Clearing the browser cache (Option b) may help in some cases, but it is not the initial troubleshooting step for slow internet connectivity. Checking for software updates (Option c) and disabling unnecessary startup items (Option d) are also good practices, but they are not directly related to resolving slow internet connectivity issues.

Explanation:
Frequent application crashes can often be resolved by updating the applications to their latest versions. Developers frequently release updates to fix bugs and improve stability. By updating the applications, the user can ensure that they are running the most stable version available.

To update applications on a Mac running OS X Yosemite 10.10, the user can follow these steps:

Open the App Store.
Click on the “Updates” tab.
If any application updates are available, click the “Update” button next to each application to update them.

Repairing disk permissions using Disk Utility (Option b) can help resolve certain issues, but it is not directly related to application crashes. Creating a new user account and testing the applications (Option c) can help determine if the issue is user-specific, but it is not the initial troubleshooting step. Resetting the NVRAM (Option d) may be necessary in some cases, but it is not the most suitable step for troubleshooting frequent application crashes.

Explanation: Frequent system crashes can often be caused by software conflicts or bugs. Therefore, the first step in troubleshooting this issue should be to check for software updates and install the latest updates. This ensures that the system is running the most stable and up-to-date software versions, which can help resolve software-related issues. Reinstalling the operating system should only be considered as a last resort if all other troubleshooting steps fail. Replacing the RAM modules may address hardware-related issues but is not the most likely cause of frequent system crashes. Clearing the NVRAM may help with certain issues but is not the recommended initial step for troubleshooting this specific problem.

Explanation: When a user is unable to connect to a specific Wi-Fi network, deleting the network from the list of known networks and reconnecting can often resolve the issue. This ensures that any incorrect or outdated network settings are cleared and allows the user to establish a fresh connection to the network. Restarting the Wi-Fi router may help in some cases, but it is not the recommended first step. Resetting the network settings on the OS X machine can be a more drastic step and should be considered if deleting and reconnecting to the network does not work. Updating the Wi-Fi driver is not necessary in this scenario, as the issue is specific to connecting to a particular network.

Explanation: Slow performance on an OS X Yosemite 10.10 machine can be caused by various factors. One common cause is having too many unnecessary startup items, which can slow down the boot process and consume system resources. Disabling unnecessary startup items can significantly improve performance. Increasing the RAM size and upgrading the processor may improve performance but require hardware changes, which may not be feasible for all users. Replacing the hard drive with an SSD can also greatly improve performance, but it is a more involved and expensive solution compared to disabling unnecessary startup items.

Explanation:

While restarting applications and the computer are basic troubleshooting steps, they may not always resolve performance issues. Verifying disk permissions using Disk Utility is a more targeted approach to identify and potentially fix permission-related problems that could be causing slow application performance.

Explanation:

Forgetting the Wi-Fi network and reconnecting forces a fresh connection establishment, potentially resolving issues related to outdated network configurations or corrupted connection settings.

Explanation: New software installations can sometimes introduce conflicts or resource consumption that leads to slow performance. Option (c) is the most targeted approach to identify if a recently installed program is causing the issue. Restarting in Safe Mode (a) might not pinpoint the exact culprit, while resetting the SMC (b) is typically used for hardware-related issues. Updating applications (d) could be helpful, but it’s not the most direct way to isolate the newly introduced software.

Explanation: Both options (a) and (b) are valuable troubleshooting steps for printing issues. Restarting the print spooler service (a) can resolve temporary glitches that might be preventing jobs from processing. Reinstalling drivers and checking paper selection (b) ensures a clean configuration and eliminates potential driver conflicts. Option (d) might be necessary later if the initial steps fail, but it’s more disruptive than (a) and (b).

Explanation: Console.app provides system logs that record various events and potential errors. By reviewing these logs, Mr. Jones might find clues about processes or hardware issues causing the freezes and slow performance. Disk Utility (a) is primarily used for disk management and repair. System Preferences (c) doesn’t offer system logs for troubleshooting. Time Machine (d) is for backups and wouldn’t directly pinpoint the cause of the issue.

Explanation: Home Sharing allows Ms. Davis to share her iTunes library with authorized devices on the same home network. AirDrop (a) is for transferring files directly between Apple devices. iCloud Music Library (b) is not available in OS X Yosemite and requires a newer macOS version. File Sharing (d) offers broader access to files and folders, but it’s not specifically designed for media sharing like Home Sharing.

Explanation: Both options (c) and (d) are crucial steps to combat potential malware. Running a reputable anti-malware application (c) can scan the system for malicious software and remove it. Additionally, changing all online account passwords (d) protects his accounts from unauthorized access if any credentials were compromised by the malware. Updating software (a) is a good practice but might not address the specific malware issue. Restarting the computer (a) might temporarily stop the pop-up ads, but it wouldn’t eliminate the root cause.