A 4-bit Johnson counter is initialized to 0101. Every time the state 1011 is reached, the counter is re-initialized to 0000 at the next clock active edge. Again when the state 0001 is reached, the counter is initialized back to 0101 at the next clock active edge. The cycle length of the counter is

A. 8

B. 16

C. 6

D. 12

Answer: Option D