Explanation
A VPN is a secure network connection that allows users to access their private corporate networks over the internet, while keeping the connection encrypted and secure. This makes it an ideal solution for providing the development team with secure connectivity from the corporate network to a three-tier cloud environment.
https://www.comptia.org/content/virtual-private-networks

Live forensics is a technique that involves investigating an active threat on a system without shutting it down or altering its state, by using tools such as memory dumpers, process explorers, registry editors, or network analyzers. Live forensics can help preserve volatile data that may be lost if the system is powered off or rebooted, such as system memory, network connections, running processes, etc. Live forensics can also help identify and stop malicious activities in real time.

Blocking the download of the file via the web proxy is the best change to make to the security tools to remedy the issue. A web proxy is a server that acts as an intermediary between a client and a web server, filtering or modifying requests and responses according to predefined rules1. Blocking the download of the file via the web proxy can prevent developers from accessing and executing the offending file that is bundled with adware. This can reduce the risk of infection or compromise of the developer workstations and improve their performance and security. Blacklisting the hash in the next-generation antivirus system (A) is not the best change to make to the security tools to remedy the issue. Blacklisting is a technique that involves blocking or denying access to known malicious or unwanted entities based on their identifiers, such as hashes, IP addresses, domains, etc2. Blacklisting the hash in the next-generation antivirus system can prevent developers from executing the offending file that is bundled with adware, but it does not prevent them from downloading it. This can still consume network bandwidth and disk space and expose developers to potential threats. Manually deleting the file from each of the workstations (B) is not the best change to make to the security tools to remedy the issue. Manually deleting the file from each of the workstations can remove the offending file that is bundled with adware, but it does not prevent developers from downloading it again. This can be a time-consuming and inefficient process that requires human intervention and coordination. Removing administrative rights from all developer workstations is not the best change to make to the security tools to remedy the issue. Removing administrative rights from all developer workstations can limit developers' ability to install or execute unauthorized or malicious applications, such as adware, but it does not prevent them from downloading them. This can also affect developers' productivity and functionality by restricting their access to legitimate applications or settings.