An ideal gas undergoes a quasi static, reversible process in which its molar heat capacity C remains constant. If during this process the relation of pressure P and volume V is given by $PV^n$=constant, then $n$ is given by (Here $C_P$ and $C_V$ are molar specific heat at constant pressure and constant volume, respectively) :

Question

( A ) $n = \frac{C_P - C}{C - C_V}$
( B ) $n = \frac{C - C_V}{C - C_P}$
( C ) $n = \frac{C - C_P}{C - C_V}$
( D ) $n = \frac{C_P}{C_V}$