Analyze Internal Difference of Each Cluster

• In XR: $X(24) - 6 = R(18)$ • In CW: $C(3/29) - 6 = W(23)$ • In TN: $T(20) - 6 = N(14)$ • In YS: $Y(25) - 6 = S(19)$ Each sub-cluster maintains a constant backward step of $-6$.

$\text{Standard pattern difference} = -6$

Check Option B (ZT - PG)

• ZT: $Z(26) - 6 = T(20)$ (matches $-6$). • PG: $P(16) - 7 = G(7)$ (difference is $-9$, not $-6$!). Therefore, ZT - PG violates the group rule.

ZT - PG is the odd one out