An amplifier without feedback has a voltage gain of 50,input resistance os 1 KΩ & Output resistance of 2.5KΩ.The input resistance of the current shunt negative feedback amplifier using the above amplifier with a feedbacik factor of 0.2 is

A. 1/11KΩ

B. 1/5KΩ

C. 5KΩ

D. 11KΩ

Answer: Option A