What will come in place of the question mark (?) in the following letter series? VX, ZB, DF, HJ, ? MCQ with Answer and Explanation

Explanation:
First: W, C, I, O, U (+6 each, wrap). Second: Z, F, L, R, X (+6 each, wrap). So UX.

Explanation:
First letters: C(3)+2=E(5), E+2=G(7), G+2=I(9), I+2=K(11), K+2=M(13). Second letters: V(22)-2=T(20), T-2=R(18), R-2=P(16), P-2=N(14), N-2=L(12). The missing cluster is ML.[reference:9]

Explanation:
First letters: I, J, K, L, M (+1). Second letters: K, L, M, N, O (+1). The next term is MO.