Answer:
Option B
Explanation:
The given sequence is a combination of two series : I. M,O,R,V and II. N, L, I, ?
The pattern in I is : $M+2 \rightarrow O, O+3 \rightarrow R, R+4\rightarrow V$
The pattern in II is : $N-2 \rightarrow L, L-3 \rightarrow I, I-4 \rightarrow E$
So, the missing letter is E.