Resolve Black Screen Issue: Missing Administrative Password

C.

The issue at hand is that a black screen is appearing and prompting the user for an administrative password every time the machine is turned on, and the technician does not have this password on file. This could be due to a variety of reasons such as a BIOS password, BitLocker encryption, or even a virus/malware.

The correct step to resolve this issue would be to remove the CMOS battery and reinsert it after ten seconds. The CMOS (Complementary Metal-Oxide-Semiconductor) is a small battery-powered chip on the motherboard that stores BIOS settings, including passwords. By removing the battery and reinserting it, the BIOS settings will be reset to their default values, which should remove any password protection.

Option A, pressing and holding the CPU power button for five seconds and then powering back on, is not a recommended step to take as it can potentially damage the hardware.

Option B, disconnecting and reconnecting the internal hard drive, is unlikely to resolve the issue as it does not address the root cause of the problem.

Option D, removing the motherboard and placing it back into the machine after ten minutes, is an extreme step that is not necessary to resolve this issue. It is also risky as it involves disassembling the computer, which can lead to hardware damage or other issues.

Therefore, option C, removing the CMOS battery and reinserting it after ten seconds, is the correct step to take to resolve the issue of the black screen prompting for an administrative password.