Multifactor authentication will be forced for Wi-Fi after deploying a client certificate to be used for Wi-Fi access for all devices in an organization3 Reference:
CompTIA Security+ (Plus) Practice Test Questions | CompTIA. Retrieved from https://www.comptia.org/training/resources/comptia-security-practice-tests

The technician should change the default administrative password FIRST to ensure the network equipment is secured against external threats on the Internet. Changing the default administrative password is a basic security measure that can help prevent unauthorized access to the network equipment. Locking all devices in a closet is a physical security measure that can help prevent theft or damage to the devices, but it does not address external threats on the Internet. Ensuring all devices are from the same manufacturer is not a security measure and does not address external threats on the Internet. Installing the latest operating system and patches is important for maintaining the security of the network equipment, but it is not the first action the technician should take1

The IT manager is most likely to be concerned about network utilization being significantly increased due to the size of CAD files. Backing up all CAD files to the software's cloud server can result in a large amount of data being transferred over the network, which can cause network congestion and slow down other network traffic.

Disk encryption should be used to secure the workstation in case of theft. Disk encryption can help to protect data on the hard drive by encrypting it so that it cannot be accessed without the correct encryption key.

The newly installed OS is x86. The x86 version of Windows 10 can only use up to 4GB of RAM. The x64 version of Windows 10 can use up to 2TB of RAM1.