Microsoft Remote Assistance (MSRA) is the correct tool to use in this scenario because it allows the technician to view the user's screen and, with the user's permission, take control of the workstation. This supports the corporate security policy that requires user supervision during remote assistance sessions. On the other hand, although Remote Desktop Protocol (RDP) does provide remote access capabilities, it does not inherently ensure the user is supervising the session, which could be against corporate security policies. Unattended remote access is commonly used for server maintenance rather than ad-hoc user support and goes against the security requirement for supervision. Skype is not primarily a remote assistance tool and does not provide the level of control or functionality required for troubleshooting in this scenario.