Correct option is A
Given: FCBF is related to EBAE and XUTX is related to WTSW with same logic.

Logic: Letters are decreasing - 1 place.
For, FCBF → EBAE
F - 1 → E, C - 1 → B, B - 1 → A, F - 1 → E
For, XUTX → WTSW
X - 1 → W, U - 1 → T, T - 1 → S, X - 1 → W
Similarly,
NKJN → ?
N - 1 → M, K - 1 → J, J - 1 → I, N - 1 → M
So, the NKJN is related to MJIN.
Thus, correct option is (a).