In the following question, a series of three letter groups is given: C A E, F D H, I G K, ? Select the group of letters that best continues this pattern based on positions in the English alphabet.

Introduction / Context:
This is another alphabet series problem where each term consists of three letters separated by spaces. The series is C A E, F D H, I G K, followed by a missing term. The task is to find a consistent relationship between corresponding letters of successive terms and then extend that relationship to obtain the next group. It is a direct test of your ability to translate letters into numeric positions and recognise fixed step patterns across columns.

Given Data / Assumptions:

• Series: C A E, F D H, I G K, ? • Options: L J N, O M Q, K L M, P O N • Alphabet positions: A 1, C 3, D 4, E 5, F 6, G 7, H 8, I 9, J 10, K 11, L 12, M 13, N 14, O 15, P 16. • Assumption: Each column of letters follows a uniform arithmetic progression in terms of positions.

Concept / Approach:
We treat each triplet as three separate sequences running in parallel. The first letters form one sequence, the second letters another, and the third letters a third sequence. If each of these sequences follows a consistent step pattern, we can extend them simultaneously to build the next triplet. This approach helps avoid confusion and provides a systematic framework for solving multi letter series questions.

Step-by-Step Solution:
Step 1: First letters: C, F, I. Positions are 3, 6, and 9. The difference between each pair is +3. Step 2: Extend the first letter sequence: 9 + 3 = 12, which is L. Step 3: Second letters: A, D, G. Positions are 1, 4, and 7. Here also the difference is +3 each time. Step 4: Extend the second letter sequence: 7 + 3 = 10, which is J. Step 5: Third letters: E, H, K. Positions are 5, 8, and 11. Again, the step is +3 each time. Step 6: Extend the third letter sequence: 11 + 3 = 14, which is N. Step 7: Combining the three predicted letters gives L J N as the missing term.

Verification / Alternative check:
We can list the triplets with numeric positions grouped by columns: first column (3,6,9,12), second column (1,4,7,10), and third column (5,8,11,14). Each column is clearly an arithmetic progression with common difference +3. Converting the final column entries back to letters yields L for 12, J for 10, and N for 14, which matches option L J N. No other option maintains a +3 increment in all three columns.

Why Other Options Are Wrong:
O M Q does not fit because its first letter O is position 15, which would represent a +6 jump from I, breaking the +3 pattern. K L M would move the first letter backward from I to K (11), which is inconsistent with repeated forward jumps of +3. P O N breaks both the first and second letter sequences when converted to positions.

Common Pitfalls:
One common error is to look for a single relationship among all three letters taken together, rather than breaking them into separate columns. Another is to miscalculate a position or a difference, which then leads to a wrong pattern. Writing the positions and checking differences systematically ensures you spot the correct arithmetic progression and avoid guesswork.

Final Answer:
The group of letters that correctly continues the series is L J N.