$A$ resistor of $50 \Omega$,an inductor of self-inductance $\left(\frac{3}{\pi^2}\right) H$,and a capacitor of unknown capacity are connected in series to an a.c. source of $100 \ V$ and $50 \ Hz$. When the voltage and current are in phase,the value of capacitance is (nearly):

• A
  $0.66 \times 10^{-4} \ F$
• B
  $0.33 \times 10^{-4} \ F$
• C
  $0.66 \times 10^{-2} \ F$
• D
  $0.33 \times 10^{-2} \ F$