Circuit with three capacitors

The above diagram is a circuit that consists of three capacitors A , B and C with capacitances $C_0,$ $C_0$ and $2C_0,$ respectively, and a resistor with resistance R . The voltage of the power supply, $V,$ is constant. Which of the following statements is correct?

a) When the switch S is open, the charged electricity of the capacitor A is twice as large as that of the capacitor B .
b) When the switch S is closed, the charged electricity of the capacitor C is twice as large as that of the capacitor B .
c) The electric energy charged on the capacitor A when the switch S is open is the same as that when the switch S is closed.