In this alphabet pattern question, find the odd group of letters from the given alternatives based on the constant step between consecutive letters.

Introduction / Context:
This non verbal reasoning question involves groups of three letters. The aim is to identify which group of letters does not follow the same alphabetic stepping pattern as the others. These types of problems train your ability to recognize consistent increases or decreases in letter positions, which is a vital part of coding decoding and series questions.

Given Data / Assumptions:
- The letter groups are LJH, XUS, VTR, and FDB.- All letters belong to the English alphabet.- The order and spacing of letters in each group is the key to the pattern.

Concept / Approach:
A systematic way to attack these questions is to convert each letter into its numeric position and then find the difference between consecutive letters in the group. If three groups show the same constant step size and one group does not, that group is the odd one out. Here, we will examine whether the letters are moving backward in the alphabet by a fixed number of positions.

Step-by-Step Solution:
Step 1: In LJH, the letters are L, J, H. Their positions are 12, 10, and 8. Differences are minus 2 and minus 2.Step 2: In VTR, positions are V = 22, T = 20, R = 18. Differences are minus 2 and minus 2 again.Step 3: In FDB, positions are F = 6, D = 4, B = 2. Differences are minus 2 and minus 2.Step 4: In XUS, positions are X = 24, U = 21, S = 19. Differences are minus 3 and minus 2, so the steps are not equal.Step 5: Therefore, three groups show a constant backward step of minus 2 between letters, while XUS has an uneven pattern.

Verification / Alternative check:
You can also recite the letters. LJH goes backward skipping one letter each time, as does VTR and FDB. However, XUS does not follow a simple skip one backward pattern, which confirms that it is different from the rest.

Why Other Options Are Wrong:
LJH: Forms a regular backward sequence with a minus 2 step.VTR: Follows the same minus 2 backward pattern.FDB: Also a backward sequence with constant minus 2 steps.

Common Pitfalls:
Some candidates only check whether letters are decreas­ing and ignore whether the gap is constant. However, the key is that the size of the step must match across the groups, not just the general direction.

Final Answer:
The odd letter group is XUS because it does not follow the constant minus 2 backward step pattern that the other groups follow.