Select the combination of letters that when sequentially placed in the blanks of the given series will complete the series.
_Q_SP_R__Q__P_R_

A

P, R, Q, 5, P, R, S, Q, S

B

P, R, Q, S, P, R, R, P, Q

C

S, P, R, S, P, R, Q, Q, S

D

P, R, Q, S, Q, S, P, R, S