Which one of the following gain equations is correct for a MOSFET common-source amplifier?(gm is mutual conductance, and RD is load resistance at the drain)

Which one of the following gain equations is correct for a MOSFET comm

1.	Which one of the following gain equations is correct for a MOSFET common-source amplifier?(gm is mutual conductance, and RD is load resistance at the drain)
A.	AV = gm/(1 - RD)
B.	AV = gm/RD
C.	AV = gm/(1 + RD)
D.	AV = RD/gm
Answer» C. AV = gm/(1 + RD)