Based on the English alphabetical order, three of the following four letter-clusters are alike in a certain way and thus form a group. Which is the one that DOES NOT belong to that group?

(Note: The odd one out is not based on the number of consonants/vowels or their position in the letter-cluster.)​​

Let's check each options:

K +2 → M

M -5 → H

G +2 → I $$\not=$$ D

D -5 → Y $$\not=$$ H 

Q +2 → S

S -5 → N

H +2 → J

J -5 → E

All options except GDH follow the pattern +2, then -5 in letter positions.​

So,  Odd one out: GDH

Thus, the correct option is: (b)