In the following series, only one letter-cluster is wrong. Choose the wrong letter-cluster.YCG, IMQ, SVZ, CGK, MQU

Series:

YCG, IMQ, SVZ, CGK, MQU

Check letter positions:

• Y = 25, C = 3, G = 7
• I = 9, M = 13, Q = 17
• S = 19, V = 22, Z = 26
• C = 3, G = 7, K = 11
• M = 13, Q = 17, U = 21

Observe correct pattern within each cluster:

Each letter increases by $+4$:

• Y → C (+4 cyclic), C → G (+4) ✅
• I → M (+4), M → Q (+4) ✅
• C → G (+4), G → K (+4) ✅
• M → Q (+4), Q → U (+4) ✅

For SVZ:

S → V = +3
V → Z = +4

This breaks the pattern.

So the wrong letter-cluster is SVZ.

Correct Answer: SVZ