In the alphabet series C, E, G, J, M, Q, ?, choose the letter that correctly completes the pattern.

Introduction / Context:
This question checks the ability to recognise a pattern in the positions of letters in the English alphabet. The letters do not increase with a constant step size, so we must look carefully at how the gaps between successive letters change as the series progresses.

Given Data / Assumptions:

• Series given: C, E, G, J, M, Q, ?
• C is the 3rd letter, E is the 5th, G is the 7th, J is the 10th, M is the 13th, Q is the 17th.
• We assume the same hidden rule that generates earlier terms also generates the missing term.

Concept / Approach:
The key idea is to convert each letter into its numerical position in the alphabet and then inspect the differences between successive positions. Once a pattern of differences is found, we extend it to find the position of the missing letter and then convert that back to an alphabetic character.

Step-by-Step Solution:
Step 1: Replace letters by positions: C=3, E=5, G=7, J=10, M=13, Q=17.Step 2: Find the differences between consecutive terms: 5 - 3 = 2, 7 - 5 = 2, 10 - 7 = 3, 13 - 10 = 3, 17 - 13 = 4.Step 3: The differences follow the pattern 2, 2, 3, 3, 4, so the next difference should again be 4.Step 4: Add 4 to the last known position: 17 + 4 = 21.Step 5: The 21st letter of the alphabet is U, so the missing term is U.

Verification / Alternative check:
Write the sequence of differences explicitly as pairs: two 2s, then two 3s, then 4. It suggests a pattern of repeating each step size twice before increasing it by 1. Extending that logic gives another 4, which leads exactly to position 21 and thus to the letter U. This confirms internal consistency.

Why Other Options Are Wrong:
Letters like T, P, V or S do not correspond to adding the correct difference of 4 to the last position. For example, T is position 20 (difference 3), and V is position 22 (difference 5). These break the observed repeated difference pattern and therefore cannot be correct.

Common Pitfalls:
Some learners only look for a single constant step, such as adding 2 or adding 3, and conclude that no clear pattern exists. In alphabet series questions, step sizes can themselves follow a pattern, such as repeating or gradually increasing. Ignoring this second layer leads to wrong answers.

Final Answer:
The letter that correctly completes the series is U.