Which of the following statements about parallel plate capacitors is/are correct?

I. Capacitance of the capacitor  is inversely proportional to the distance between the plates

II. Capacitors can filter a.c signals from d.c 

III. Capacitors can store charges

A.

I only

B.

I and II only

C.

II and III only

D.

I, II and III

Correct answer is C

Capacitors pass AC but block DC signals (when charged up to the applied DC voltage), they are often used to separate the AC and DC components of a signal. Capacitors are also primarily used to store energy.