Two Identical 2 $\varOmega$ Resistors Are Parallel to Each Other,and the Combination Is in the Combination

Multiple Choice

Two identical 2.5- $\varOmega$ resistors are parallel to each other,and the combination is in series with a 5.0-nF capacitor,in a circuit with a switch open.If initially 15.0 V is across the capacitor,how long after the switch is closed will the voltage across the resistor pair be 2.5 V?

A) 1.1 ns
B) 11 ns
C) 4.4 ns
D) 44 ns