Classification – Odd one out (alphabet order): Choose the string unlike the others: RQP, HGF, NPR, DCB.

Introduction / Context:
Triplets built from consecutive letters typically move strictly in one direction (ascending or descending). The odd member will violate that monotonic direction.

Given Data / Assumptions:

• Strings: RQP, HGF, NPR, DCB.
• Standard alphabet ordering assumed.

Concept / Approach:
Check whether each triplet is strictly descending by 1. If three are descending and one is not, that non-descending triplet is the outlier.

Step-by-Step Solution:
RQP: R→Q→P (−1 each) – descending.HGF: H→G→F (−1 each) – descending.DCB: D→C→B (−1 each) – descending.NPR: N→P (+2), P→R (+2) – ascending by 2, not descending by 1.

Verification / Alternative check:
Index mapping (A=1 …): R(18),Q(17),P(16); H(8),G(7),F(6); D(4),C(3),B(2); N(14),P(16),R(18). Only NPR increases.

Why Other Options Are Wrong:

• RQP, HGF, DCB all share the same descending-by-1 pattern.

Common Pitfalls:
Letting the symmetry of NPR (letters two apart) distract from the dominant monotonic direction that groups the other three.

Final Answer:
NPR