Letter pair series AB BC CD DE – UGC NET Question

Each pair is formed by two consecutive letters, and the starting letter of each pair moves forward by one each time: AB, BC, CD, DE. After DE, the next consecutive pair should begin with E and include F, giving EF. Thus EF continues the sliding two-letter window.

Option A:
Option A, FG, is also a pair of consecutive letters but starts at F. It skips the pair that should begin at E, which the pattern requires. Because the series moves the starting letter by only one position at a time, FG is too far ahead.

Option B:
Option B is correct because EF starts at E, the letter immediately following D, and includes F. It preserves the same length and consecutive-letter property as the earlier terms. This perfect alignment with the rule makes EF the valid next term.

Option C:
Option C, DE, merely repeats the last pair in the series. The pattern is strictly forward-moving and does not suggest repetition. Hence DE cannot be considered the next item.

Option D:
Option D, CD, goes backward, returning to an earlier pair. This contradicts the continuous forward shift of the starting letter. As a result, CD does not logically follow DE in this sequence.