In the following mixed series of numbers and letters, 63 O 49 72 T 37 96 L 15 14 ? 58, which alphabet should replace the question mark so that the underlying pattern remains consistent throughout the series?

Introduction / Context:
This question is a number and alphabet series puzzle, which is commonly used in aptitude tests to check pattern recognition. The series 63 O 49 72 T 37 96 L 15 14 ? 58 has both numbers and letters, and the task is to identify the missing letter that preserves the logic of the sequence. Understanding how numbers and letters interact in such patterns is essential for exam performance in reasoning sections.

Given Data / Assumptions:

The series mixes pairs of numbers with single letters between them.
The pattern relating numbers to the letter between them is consistent across each triplet (number, letter, number).
We must use the existing combinations 63 O 49, 72 T 37 and 96 L 15 to deduce the rule.
The same logic then has to be applied to 14 ? 58 to find the missing letter.

Concept / Approach:
The strategy is to treat each letter as a coded representation of the two surrounding numbers. We examine how 63 and 49 relate to O, how 72 and 37 relate to T, and how 96 and 15 relate to L. These relationships typically use arithmetic operations such as addition, subtraction or differences, which are then converted into a letter position in the alphabet. Once the relationship is discovered, it can be applied to the final pair 14 and 58 to determine which alphabet must fill the gap.

Step-by-Step Solution:

Verification / Alternative check:
An alternative way to be confident in the answer is to test the discovered rule in reverse or compare it with number letter relationships in other reasoning questions. When you recheck each triplet using the rule you have adopted, all three earlier triplets and the final one agree with the same logic, producing O, T, L and then C. This internal consistency is what confirms that C is the only letter that maintains the established structure of the series.

Why Other Options Are Wrong:

A does not match the calculated alphabetical position derived from the pair 14 and 58 and would break the pattern that exists in the earlier parts of the series.
B similarly fails to satisfy the relationship between the numbers flanking the letter and therefore cannot represent the same coding rule used for O, T and L.
D also does not match the numeric to alphabet conversion that is consistent in the previous triplets, so inserting D would destroy the logical cohesiveness of the series.

Common Pitfalls:
Students often attempt to spot very simple patterns, such as direct differences between adjacent numbers, and ignore the possibility of more subtle relationships such as half differences, averages or double steps. Another mistake is focusing only on forward arithmetic without examining bidirectional patterns. It is always important to test any guessed rule on all existing segments of the series before applying it to the missing term.

Final Answer:
The alphabet that should replace the question mark to preserve the series pattern is C.