Four letter-clusters have been given, out of which three are alike in some manner and one is different. Select the one that is different. (Note: The odd one out is not based on the number of consonants/vowels or their position in the letter cluster)
1) FGNOP
2) IJQRS
3) OPWXY
4) RSXYZ

Logic: All follow the pattern +1, +7, +1, +1
1) FGNOP
F +1 → G, G +7 → N, N +1 → O, O +1 → P
2) IJQRS
I +1 → J, J +7 → Q, Q +1 → R, R +1 → S
3) OPWXY
O +1 → P, P +7 → W, W +1 → X, X +1 → Y
4) RSXYZ
R +1 → S, S +7 → Z, Z +1 → A$$\neq$$ X, X +1 → Y
Since RSXYZ does not follow the pattern correctly, the odd one out is: RSXY

Thus, correct option is (c).