Correct option is C
Given: HMI 3, JOK 6, LQM 9, NSO 12, ?
Logic:

Letters increased by +2 each position:
HMI → JOK → LQM → NSO → ?
Numbers increase by +3: 3, 6, 9, 12 ..
1st Letter:
H + 2 = J, J + 2 = L, L + 2 = N, N + 2 = P
2nd Letter:
M + 2 = O, O + 2 = Q, Q + 2 = S, S + 2 = U
3rd Letter:
I + 2 = K, K + 2 = M, M + 2 = O, O + 2 = Q
Number:
3 → 6 → 9 → 12 → 15
So, ? = PUQ 15
Thus, the correct option is (C) PUQ 15