Classification – Odd one out (5-letter chains with +2, +3, +4, +5): Which sequence fails the progressive step pattern +2, +3, +4, +5: DFIMR, CEHLQ, GILPU, HJMPT?

Introduction / Context:
Five-letter chains often encode steadily growing forward steps. Here the intended pattern is: from letter1 to letter2 add +2; letter2→letter3 add +3; letter3→letter4 add +4; letter4→letter5 add +5. Three options follow this staircase. One breaks it and is the outlier.

Given Data / Assumptions:
Using A=1 … Z=26:

• DFIMR → D(4)→F(6)=+2; F(6)→I(9)=+3; I(9)→M(13)=+4; M(13)→R(18)=+5.
• CEHLQ → C(3)→E(5)=+2; E(5)→H(8)=+3; H(8)→L(12)=+4; L(12)→Q(17)=+5.
• GILPU → G(7)→I(9)=+2; I(9)→L(12)=+3; L(12)→P(16)=+4; P(16)→U(21)=+5.
• HJMPT → H(8)→J(10)=+2; J(10)→M(13)=+3; M(13)→P(16)=+3 (should be +4); P(16)→T(20)=+4 (should be +5).

Concept / Approach:
Compute successive differences and match against the target staircase. HJMPT loses one step of growth partway through, so it fails the +2,+3,+4,+5 requirement.

Step-by-Step Solution:
1) Calculate the four gaps for each sequence.2) Confirm DFIMR/CEHLQ/GILPU follow +2, +3, +4, +5.3) Identify HJMPT as the rule-breaker due to +2, +3, +3, +4.

Verification / Alternative check:
Reverse-direction checks still reveal the same inconsistency in HJMPT’s internal spacing.

Why Other Options Are Wrong:
They maintain the exact progressive step pattern throughout.

Common Pitfalls:
Stopping after checking only the first two gaps. The later gaps (+4, +5) are crucial to confirm rule adherence.

Final Answer:
HJMPT