Select the option in which the pair of letter-clusters share the same relationship as that shared by the given pair of letter-clusters.

LAB : BAL :: ?

ONM : MNO

A   B   C    D   E    F   G    H    I    J    K    L   M

 ↓    ↓    ↓    ↓    ↓     ↓   ↓    ↓     ↓   ↓    ↓    ↓    ↓

 Z   Y    X   W   V    U   T    S    R   Q   P    O   N

26  25  24  23  22  21  20  19  18  17  16  15  14

******************************************

LAB : BAL :: ?

The  logic followed here is :

LAB

WRITTEN IN BACKWARD FORMAT

LAB = BAL

SIMILARLY

ONM

WRITTEN IN BACKWARD FORMAT

ONM = MNO