A letter series is given with one term missing. Choose the correct letter that will complete the sequence: L, N, Q, S, V, ?

Introduction / Context:
This is another single-letter series question that checks your ability to track non-uniform increments in the alphabet. The sequence is L, N, Q, S, V, ?, and the goal is to find the letter that should appear next based on the pattern of jumps between letters.

Given Data / Assumptions:

• Series: L, N, Q, S, V, ?
• Each term is one letter.
• The pattern is based on alphabetical positions.
• Alphabet positions: A = 1, ..., Z = 26.

Concept / Approach:
We convert each letter into its position in the alphabet and then examine the differences between consecutive terms. It is common in such series to alternate step sizes, for example +2, +3, +2, +3 and so on. Once the pattern is identified, we use it to generate the next position and convert back to a letter.

Step-by-Step Solution:
Step 1: Convert letters to positions. L = 12, N = 14, Q = 17, S = 19, V = 22. Step 2: Compute the differences between terms. From 12 to 14: +2. From 14 to 17: +3. From 17 to 19: +2. From 19 to 22: +3. Step 3: The pattern is +2, +3, +2, +3, alternating between +2 and +3. Step 4: Following the alternation, the next difference should be +2 (since the last was +3). Step 5: Apply +2 to the last known term: 22 + 2 = 24. Step 6: Position 24 corresponds to the letter X.

Verification / Alternative check:
Rewrite the series including the answer: L (12), N (14), Q (17), S (19), V (22), X (24). The differences are +2, +3, +2, +3, +2, which neatly preserves the alternating pattern. Thus X is the correct continuation.

Why Other Options Are Wrong:
Option A (W): W is 23; 22 to 23 is +1, which does not match the +2 or +3 pattern. Option B (Y): Y is 25; 22 to 25 is +3, which would break the alternating sequence by repeating +3 twice in a row. Option C (Z): Z is 26; 22 to 26 is +4, which does not fit any part of the established pattern.

Common Pitfalls:
A frequent mistake is to look for a single fixed difference and, when it is not found, to guess randomly. Another is to misread the pattern and think it is simply increasing differences, instead of noticing that the series alternates between two values. Always list out the exact differences to detect alternations or cycles.

Final Answer:
The letter that correctly completes the series is X, which corresponds to option D.