Three of the following four letter-clusters are alike in a certain way and one is different.
Pick the odd one out.
(NOTE: The odd one out is not based on the number of vowels or consonants in the word)

​Now, let's check each option:

a) GHDV:

G + 1 = H 

D + V = 4 + 22 = 26 

b)  LMIQ:

L + 1 = M 

I + Q = 9 + 17 = 26 

c)  STPJ:

S + 1 = T 

P + J = 16 + 10 = 26

d) NOPQ:

N + 1 = O 

P + Q = 16 + 17 = 33 ≠ 26

So, odd one out is option (d).

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