What should come next in the following letter sequence?

A A B A B C A B C D A B C D E A B C D

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

AK, CO, ES, ?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

PEN, MBK, JYH, GVE, ?

Which of the following terms follows the trend of the given list?

BAAAAAA, AAAAAAB, ABAAAAA, AAAAABA, AABAAAA, _______________.

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

XJ, WL, VN, UP, ?

Which set of letters when sequentially placed at the gaps in the given letter series shall complete it?

NO_PQN_PP_NOP_Q

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

OK, SN, WQ, AT, ?

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.

JD,?,QK, VP, BV

Which set of letters when sequentially placed at the gaps in the given letter series shall complete it?

a_b_cc_a_b_c