From the following three-letter sequences, which one is the odd one out based on the alphabetical order of the letters?

Introduction / Context:
This odd one out question uses three letter sequences. The goal is to identify a consistent pattern in most of the options and then find which one breaks that pattern. The sequences are built from consecutive letters of the English alphabet arranged in a certain order. Recognising the direction and spacing of the letters allows you to quickly see which group does not match the others.

Given Data / Assumptions:

• Given sequences: WVU, DBA, NML, HGF, TSR.
• We assume the standard English alphabet with positions A = 1, B = 2, C = 3, ..., Z = 26.
• We look for ascending or descending consecutive patterns.

Concept / Approach:
Start by examining whether the letters in each triplet move forward or backward through the alphabet in a regular way. For WVU, W is followed by V and then U. In terms of positions: W (23), V (22), U (21). These are three consecutive letters in descending order. For NML, N (14), M (13), L (12) is again a sequence of three consecutive letters in descending order. Similarly, HGF gives H (8), G (7), F (6), which is also three consecutive letters descending. TSR gives T (20), S (19), R (18), again three consecutive letters descending. Only DBA does not follow this pattern.

Step-by-Step Solution:

Step 1: Write the positions for WVU: W = 23, V = 22, U = 21. This is a smooth sequence 23, 22, 21. Step 2: For NML, N = 14, M = 13, L = 12, forming 14, 13, 12, again a descending sequence of consecutive letters. Step 3: For HGF, H = 8, G = 7, F = 6, again three consecutive descending positions. Step 4: For TSR, T = 20, S = 19, R = 18, giving 20, 19, 18, another descending consecutive sequence. Step 5: For DBA, D = 4, B = 2, A = 1, which corresponds to 4, 2, 1, not three consecutive numbers and not a smooth step of 1 down each time. Step 6: Conclude that DBA is the only sequence that does not consist of three consecutive letters in descending order.

Verification / Alternative check:
Double check that there is no alternative pattern that could isolate a different option. WVU, NML, HGF, and TSR all show equally spaced steps of minus one between letters. For DBA, the change from D to B skips C (it is a step of minus two), and from B to A is a step of minus one. Because the pattern is inconsistent and the numbers are not consecutive, DBA clearly stands apart from the others. No other option breaks the straightforward descending sequence rule.

Why Other Options Are Wrong:
WVU, NML, HGF, and TSR all correctly follow the pattern of three letters that are alphabetically consecutive and arranged in reverse (descending) order. As such, they belong to the same group. They cannot be the odd one out because they perfectly match the discovered rule. Only DBA fails to match, since it has an uneven gap between letters.

Common Pitfalls:
Sometimes candidates fixate on the actual letters rather than the pattern, wondering whether there is some hidden word or abbreviation. Others may overlook TSR because it is not in the original list they expected, but it still fits the pattern perfectly. A systematic approach of converting letters to positions and checking for equal steps prevents such mistakes.

Final Answer:
The sequence that does not follow the pattern of three consecutive letters in descending order is DBA, so DBA is the odd one out.