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.)

Correct option is D

Information Given:
A: WN – TZ
B: VM – SY
C: XO – UA
D: PG – NS

Logic:
First letter: −3
Second letter: +12 (cyclic)

Explanation:
WN → TZ
W → T (−3) ✔
N → Z (+12) ✔

VM → SY
V → S (−3) ✔
M → Y (+12) ✔

XO → UA
X → U (−3) ✔
O → A (+12) ✔

PG → NS
P → N (−2) ✘
G → S (+12) ✔
Only PG – NS does not follow the common pattern.

Final Answer:
PG – NS

Final Correct Option:
D