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 letter-cluster 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.)

Logic: 1st letter - 4 = 2nd letter and 2nd letter + 7 = 3rd letter
Now, we check each options.
​Option (a): HDK (Follow)

H - 4 = D, D + 7 = K
​Option (b): ​FBJ​ (Not Follow)​

F - 4 = B, B + 7 $$\neq$$​ J
​Option (c): MIP (Follow)​

M - 4 = I, I + 7 = P
​Option (d): ​JFM​ (Follow)​

J - 4 = F, F + 7 = M
Thus, correct option is (b). ​​​