From the letter pairs MG, QK, VN and UO, find the odd pair based on the fixed gap between letters.

Introduction / Context:
Letter pair questions often hide a simple numeric relationship between the positions of the two letters in the alphabet. Typical relationships include a fixed forward or backward gap. To solve such questions efficiently, candidates must convert letters to numeric positions and then look for a consistent pattern. In this problem, we are given four pairs of letters and asked to find which pair does not follow the same positional gap rule as the others.

Given Data / Assumptions:
The letter pairs are MG, QK, VN and UO. We take A = 1, B = 2, ..., Z = 26 as the positions in the English alphabet. We compare the difference between the first and second letters in each pair.

Concept / Approach:
The primary concept is the fixed difference between letter positions. We calculate the difference first letter position minus second letter position, or simply the absolute difference, and check whether most pairs share the same value. If three pairs have the same difference (for example 6) and one has a different difference (for example 8), the pair with the different gap is the odd one out. This kind of pattern is common in reasoning sections and is easy to handle once you practice converting letters to numeric positions quickly.

Step-by-Step Solution:
Step 1: For MG, M is the 13th letter and G is the 7th letter. Difference = 13 - 7 = 6. Step 2: For QK, Q is the 17th letter and K is the 11th letter. Difference = 17 - 11 = 6. Step 3: For UO, U is the 21st letter and O is the 15th letter. Difference = 21 - 15 = 6. Step 4: For VN, V is the 22nd letter and N is the 14th letter. Difference = 22 - 14 = 8. Step 5: Three pairs have a fixed difference of 6, while one pair has a difference of 8. Therefore VN is the pair that breaks the pattern.

Verification / Alternative check:
We can quickly recheck each position to avoid errors: positions M = 13, G = 7, Q = 17, K = 11, V = 22, N = 14, U = 21 and O = 15 are standard. Recomputing confirms differences: MG has 6, QK has 6, UO has 6 and VN has 8. Since these are straightforward arithmetic operations, the pattern is robust and unambiguous.

Why Other Options Are Wrong:
MG is not the odd one out because it satisfies the common difference rule of 6. QK is not the odd one out because it also has a difference of 6 and belongs to the same group. UO is not the odd one out because its letter difference is again 6, consistent with MG and QK. Only VN has a different positional gap of 8, so it is the odd member.

Common Pitfalls:
A common mistake is to look for alphabetical order direction (forward or backward) only, ignoring the actual magnitude of the gap. Some candidates may try to form meaningful abbreviations or words out of the pairs instead of checking the numeric pattern, which is not the intent in such reasoning questions. Systematically converting letters to numbers and immediately testing small differences like 2, 3, 4 or 6 helps solve these quickly and accurately.

Final Answer:
The letter pair that does not follow the fixed gap of 6 and is therefore the odd one out is VN.