[单选题]
The power factor of an RLC cirkb9 k6hc, hgo,rhh(cn ij )/k6cuit is defin k1i2yhz ( nz27oc9luned as $\cos M = R/Z$, but the phase angle can also be calculated from .
A. $\sin M = (X_L - X_C)/Z$
B. $\sin M = (X_L - X_C)/RZ$
C. $\sin M = Z/(X_L - X_C)$
D. $\sin M = RZ/(X_L - X_C)$
