Correct option is C
Given: EDC, JIH, ONM, TSR, ?

Logic: Letters are increaisng + 5 place.
E + 5 = J, J + 5 = O, O + 5 = T, T + 5 = Y
D + 5 = I, I + 5 = N, N + 5 = S, S + 5 = X
C + 5 = H, H + 5 = M, M + 5 = R, R + 5 = W
So, the missing term is YXW.
Thus, correct option is (c).