In Order for a Circuit to Respond Quickly,its Time Constant

Multiple Choice

In order for a circuit to respond quickly,its time constant should be short.In a circuit involving resistance and capacitance,which of the following choices would result in the shortest time constant?

A) R = 75 Ω,C = 75 μF
B) R = 200 Ω,C = 200 μF
C) R = 300 Ω,C = 75 μF
D) R = 100 Ω,C = 30 μF