Which of the following measurements is an example of an appropriate use of a Multimeter when troubleshooting a Mac?

A.
Measure logic board battery voltage.

B.
Measure amount of ESD voltage in the area.

C.
Measure digital signals on the main processor.

D.
Measure amount of AC volts going to the hard drive or SSD.

Explanation:
http://www.wikihow.com/Use-a-Multimeter