Based on the English alphabetical order, three of the following four letter-cluster pairs are alike in a certain way and thus form a group. Which letter-cluster pair 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)​

Lets check each options

A) P − 2 = N, S − 2 = Q

B) E − 2 = C, H − 2 = F
C) K − 2 = I, N − 2 = L
D) G − 1 = F, J + 1 = K
All have −2 for both letters except D (GJ–FK).​​

Thus, correct option is (d).