In a 4 bit ripple counter using flip flops with tpd = 40 ns, the maximum frequency can be

In a 4 bit ripple counter using flip flops with tpd = 40 ns, the maxim

1.	In a 4 bit ripple counter using flip flops with tpd = 40 ns, the maximum frequency can be
A.	1.25 MHz
B.	3.25 MHz
C.	6.25 MHz
D.	12.5 MHz
Answer» D. 12.5 MHz