Based on the English alphabetical order, three of the following four…
2026
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 is the one that 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.)
Answer: D. MO−PU — Concept: A letter-cluster odd-one-out set is settled by arithmetic on alphabet positions (A = 1, B = 2, ..., Z = 26), not by reading the letters as words. For…
- A.
WY−AC
- B.
PR−TV
- C.
BD−FH
- D.
MO−PU
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Correct answer: D
Concept: A letter-cluster odd-one-out set is settled by arithmetic on alphabet positions (A = 1, B = 2, ..., Z = 26), not by reading the letters as words. For a pair of clusters, two quantities describe the relation completely: the gap between the letters inside each cluster, and the number of places one must move forward through the alphabet, wrapping from Z back to A, to travel from a letter of the first cluster to the matching letter of the second. Options that share both quantities belong to the same group.
Application: writing every option in that form gives the following.
Pair | First cluster (positions) | Second cluster (positions) | Gap inside each cluster | Forward shift (1st letter, 2nd letter) |
|---|---|---|---|---|
WY − AC | 23, 25 | 1, 3 | 2, 2 | +4, +4 |
PR − TV | 16, 18 | 20, 22 | 2, 2 | +4, +4 |
BD − FH | 2, 4 | 6, 8 | 2, 2 | +4, +4 |
MO − PU | 13, 15 | 16, 21 | 2, 5 | +3, +6 |
Cross-check: the same grouping can be read straight off the alphabet, because taking every second letter reproduces it.
W, Y, A, C are alternate letters of the alphabet, running past Z and continuing from A.
P, R, T, V are alternate letters of the alphabet.
B, D, F, H are alternate letters of the alphabet.
M, O, P, U are not: after M and O the alternating run would call for Q and S, not P and U.
Result: MO - PU is the pair that does not belong to the group. The note in the question already rules out counting vowels and consonants, and the positional arithmetic settles it: MO - PU carries internal gaps of 2 and 5 with shifts of 3 and 6 places, while the other three carry internal gaps of 2 and 2 with a uniform shift of 4 places.