The SI unit of form factor is
(A) Ampere
(B) Volt
(C) Watt
(D) None of the above

Hint: We should know that Form factor for computers refers to the size, shape, and physical specifications of hardware or hardware components. Computer form factor is used to describe any physical aspect of a computer system. Form factor is very important for connection compatibility. The shape and layout of a motherboard is called the form factor. The form factor affects where individual components go and the shape of the computer's case. There are several specific form factors that most PC motherboards use so that they can all fit in standard cases. Using this concept we have to solve this question.

Complete step-by step answer:

We should know that in electronics or electrical the form factor of an alternating current waveform (signal) is the ratio of the RMS root mean square value to the average value or mathematical mean of absolute values of all points on the waveform. The former can also be defined as the direct current that will produce equivalent heat.
The form of a factor is a measure of the scattering amplitude of a wave by an isolated atom.
Ampere is the unit of current, volt is the unit of potential difference, watt is the unit of power.
Form factor is a ratio and does not have any unit.

Hence, the correct answer is Option D.

Note: We should know that form factor for computers refers to the size, shape, and physical specifications of hardware or hardware components. Computer form factor is used to describe any physical aspect of a computer system. Form factor is very important for connection compatibility. Peak Factor is defined as the ratio of maximum value to the R.M.S value of an alternating quantity. The alternating quantities can be voltage or current. The maximum value is the peak value or the crest value or the amplitude of the voltage or current. Ripple factor (RF) of a waveform is defined as the ratio of, rms value of ac component of waveform, to the, average value of the waveform.