A 4 bit ripple counter uses flip flops with propagation delay of 50 ns each. The maximum clock frequency which can be used is

A 4 bit ripple counter uses flip flops with propagation delay of 50 ns

1.	A 4 bit ripple counter uses flip flops with propagation delay of 50 ns each. The maximum clock frequency which can be used is
A.	5 MHz
B.	10 MHz
C.	20 MHz
D.	25 MHz
Answer» B. 10 MHz