When a single user is experiencing network issues while others are unaffected, the first step should always be to check the physical connectivity. This includes verifying that the Ethernet cable is plugged in properly, the NIC is enabled, and the link lights are active.
* Option B (Reboot the router): Affects all users and is not necessary since others are not experiencing the issue.
* Option C (Disable IPv6): Unlikely to resolve the problem unless you're troubleshooting a specific IPv6- related issue.
* Option D (Check the DNS settings): A valid step if internet access is limited to name resolution problems, but start with physical connectivity first.
? Reference:
* CompTIA A+ 220-1102 Exam Objective 2.3 - "Given a scenario, troubleshoot common networking issues."
* CompTIA Troubleshooting Methodology - Step 1: Identify the problem.

System is the Control Panel utility that should be used to change the Path Environment Variable. The Path Environment Variable is a system variable that specifies the directories where executable files are located. To edit the Path Environment Variable, the technician should go to System > Advanced system settings > Environment Variables and then select Path from the list of system variables and click Edit.

Resource Monitor will help a technician identify the issue when a user reports a computer is running slow1

The Ease of Access Center is a built-in utility in Windows that provides tools and options for making a computer easier to use for individuals with disabilities, including the visually impaired. In the Ease of Access Center, the technician can turn on options like high contrast display, screen magnification, and screen reader software to help the user better interact with the computer.

Screen-sharing software is a tool that allows a technician to remotely view and control a user's screen over the internet. It can be used to troubleshoot issues with accessing an online share, as well as other problems that require visual inspection or guidance. Secure shell (SSH) is a protocol that allows remote access and command execution on another device, but it does not allow screen-sharing. Virtual private network (VPN) is a protocol that creates a secure tunnel between two devices over the internet, but it does not allow remote troubleshooting. File transfer software is a tool that allows transferring files between two devices over the internet, but it does not allow screen-sharing. Verified References: https://www.comptia.org/blog/what-is- screen-sharing-software https://www.comptia.org/certifications/a