In an ac circuit shown in fig , the supply voltage has a constant rms value v but variable frequency f. At resonance, the circuit
A. has a current I given by 1 = V/R
B. has a resonance frequency 500 Hz
C. has a voltage across the capacitor which is 1800 out of phase with that
D. has a current given by `I=(V)/(sqrt(R^(2)+((1)/(pi)+(1)/pi)^(2)))`
