In a CE amplifier the input impedance is equal to the ratio of

[A].	ac base voltage to ac base current
[B].	ac base voltage to ac emitter current
[C].	ac emitter voltage to ac collector current
[D].	ac collector voltage to ac collector current

Answer: Option A

Explanation:

Input is applied to base with emitter grounded. The input impedance is the ratio of ac base voltage to ac base current.