Alphabet Puzzle (Skipped Letters)

Question

The number of letters skipped in between adjacent letters of the series going backwards increases by one.

1. OIGDC
2. OMJFA
3. OMKIG
4. ONLKJ

According to this, when we start from back, the difference should increase by one as we move towards the starting letter of the series. But doing so is giving me a wrong answer.

I know that the correct answer should be 2, but why?

Answer 1

Here's why the answer is 2.

Write the alphabet out:

ABCDEFGHIJKLMNOPQRSTUVWYZ

Now highlight those letters found in answer 2:

ABCDEFGHIJKLMNOPQRSTUVWYZ

It is trivial to see that the letters skipped increase by one each time, from N to KL to GHI and so on. Therefore 2 satisfies the conditions in the question and is the answer.