‘NGRP’ is related to ‘JCNL’ in a certain way based on the English alphabetical order. In the same way, ‘FKLT’ is related to ‘BGHP’. To which of the following is ‘SQUO’ related, following the same logic?

Correct — D. Rule: every letter moves back 4 places in the alphabet, position by position.

NGRP to JCNL: N − 4 = J, G − 4 = C, R − 4 = N, P − 4 = L
FKLT to BGHP: F − 4 = B, K − 4 = G, L − 4 = H, T − 4 = P

Apply −4 to SQUO:
S(19) − 4 = O, Q(17) − 4 = M, U(21) − 4 = Q, O(15) − 4 = K

That gives OMQK — option (d).

Why the others are wrong

• (a)
  PNRL — This is −3 on every letter, not −4. Both worked pairs move back four places, not three.
• (b)
  PMRK — The shift alternates here — −3 on the first and third letters, −4 on the second and fourth. One rule has to cover all four positions.
• (c)
  ONQL — The same alternation the other way round, −4, −3, −4, −3. Only the leading O comes out right.

A four-letter cluster analogy is solved position by position. Convert each letter to its alphabet position, take the difference for the first worked pair, then confirm that difference on the second pair before applying it.

Two worked pairs are given precisely so a rule that happens to fit one of them can be ruled out. Both pairs here move −4 uniformly, which is the simplest case: one shift covering all four positions.

Uniform is not guaranteed. The same format at 19 Sep 2024, 09:00, Reasoning Q.11 moves +2, +2, −2, −2, so all four letters of both worked pairs are worth checking.

Key facts

• NGRP to JCNL and FKLT to BGHP are both a uniform shift of −4.
• SQUO shifted back four letters gives OMQK.
• Positions used: O=15, Q=17, S=19, U=21.

Common traps

• Deriving the rule from one worked pair and never testing it on the second
• Applying −3 instead of −4, which lands exactly on option (a)
• Counting S, R, Q, P as four steps back and stopping on P instead of O

No directly related past PYQ was found.