In the automatic reset circuit for a flip-flop, how long does it take the capacitor to completely charge?

In the automatic reset circuit for a flip-flop, how long does it take

1.	In the automatic reset circuit for a flip-flop, how long does it take the capacitor to completely charge?
A.	1 time constant (RC)
B.	2 time constants (RC)
C.	5 time constants (RC)
D.	10 time constants (RC)
Answer» D. 10 time constants (RC)