Quarantining the computer means isolating it from the network and other devices to prevent the spread of malware or ransomware. Ransomware is a type of malware that encrypts the files on a computer and demands payment (usually in cryptocurrency) to restore them. If a technician sees a file that is requesting payment to a cryptocurrency address, it is likely that the computer has been infected by ransomware. Quarantining the computer should be the first step to contain the infection and prevent further damage. Disabling System Restore, updating the antivirus software definitions, and booting to safe mode are not steps that should be done before quarantining the computer.

Quarantining the infected system is the most appropriate way to remediate the issue of an infection that the antivirus software cannot remove. Quarantining means isolating the system from the network and other devices to prevent the infection from spreading or causing further damage. Quarantining also allows the technician to perform further analysis and removal of the infection without risking the security of other systems or data.
Some of the steps involved in quarantining an infected system are:
Disconnect the system from the internet and any local network connections, such as Wi-Fi, Ethernet, Bluetooth, or USB.
Disable any file-sharing or remote access services on the system, such as Windows File Sharing, Remote Desktop, or TeamViewer.
Use a separate device to download and update the antivirus software and any other tools that may be needed to remove the infection, such as malware scanners, rootkit removers, or bootable rescue disks.
Transfer the updated antivirus software and tools to the infected system using a removable media, such as a CD, DVD, or USB flash drive. Scan the removable media for any infections before and after using it on the infected system.
Run the antivirus software and tools on the infected system and follow the instructions to delete or quarantine the infection. If the infection is persistent or complex, it may require booting the system from a rescue disk or using a Linux live disc to access and clean the system files.
After the infection is removed, restore the system to a previous clean state using System Restore, backup, or recovery partition. Scan the system again to ensure that it is clean and secure. Reconnect the system to the network and update the system and the antivirus software.
References:
How to Identify and Repair Malware or Virus Infected Computers, section 31 Uninstalling Antivirus Software, the Clean Way: 40 Removal Tools & Instructions, section 22 How to manually remove an infected file from a Windows computer3 The Official CompTIA A+ Core 2 Study Guide (220-1102), page 2194

An EULA (End-User License Agreement) is a legally binding contract between a software supplier and a customer or end-user, generally made available to the customer via a retailer acting as an intermediary. A EULA specifies in detail the rights and restrictions which apply to the use of the software. Some of the main terms included in an EULA are the terms and scope of the license, any licensing fees, warranties and disclaimers, limitation of liability, revocation or termination of the license, and intellectual property information and restrictions on using the license (e.g. modification and copying)1
https://www.termsfeed.com/blog/eula-vs-terms-conditions/

The first thing that the specialist should do to protect the company's data on an insecure network with open authentication is to connect to the vendor's network using a VPN. A VPN stands for Virtual Private Network and is a technology that creates a secure and encrypted connection over a public or untrusted network. A VPN can protect the company's data by preventing eavesdropping, interception or modification of the network traffic by unauthorized parties. A VPN can also provide access to the company's internal network and resources remotely. Manually configuring an IP address, a subnet mask and a default gateway may not be necessary or possible if the vendor's network uses DHCP to assign network configuration parameters automatically. Manually configuring an IP address, a subnet mask and a default gateway does not protect the company's data from network attacks or threats. Changing the network location to private may not be advisable or effective if the vendor's network is a public or untrusted network. Changing the network location to private does not protect the company's data from network attacks or threats. Configuring MFA on the network may not be feasible or sufficient if the vendor's network has open authentication and does not support or require MFA. Configuring MFA on the network does not protect the company's data from network attacks or threats. References: CompTIA A+ Core 2 (220-1002) Certification Exam Objectives Version 4.0, Domain 3.3

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.