An RC Series Circuit Is Connected to an Emf Source $\omega$

An RC series circuit is connected to an emf source having angular frequency $\omega$ . The current:

A) leads the source emf by tan^-1(1/ $\omega$ CR)
B) lags the source emf by tan^-1(1/ $\omega$ CR)
C) leads the source emf by tan^-1( $\omega$ CR)
D) lags the source emf by tan^-1( $\omega$ CR)
E) leads the source emf by $\pi$ /4