Which of the following letter clusters will replace the question mark(?) in the given series to make it logically complete?

DSB, GVY, JYV, MBS, ?

Given: DSB, GVY, JYV, MBS, ?

Logic: First & second letter increases by +3, and third letter decreases by -3.

Explanation:

First letter: D+3=G, G+3=J, J+3=M, M+3=P

Second letter: S+3=V, V+3=Y, Y+3=B, B+3=E

Third letter: B-3=Y, Y-3=V, V-3=S, S-3=P

So, ? is replaced by PEP

Thus, Option A is the correct answer.