Select the combination of letters that when sequentially placed in the blanks of the given series will complete the series.
s _ r _ k s _ _ c k _ u r c _ s u _ c _

A

c, u, c, r, s, k, r, k

B

u, c, u, r, s, k, r, k

C

c, u, c, s, r, k, s, k

D

u, c, u, k, r, s, r, k