Choose the set of letters that sequentially completes the following letter series.
ab _ b _ babab _ b _ bab
Show answer & explanation
Correct answer: A
Explanation
The given incomplete series has 16 positions:
ab _ b _ babab _ b _ bab
By placing a, a, a, a (from Option A) in the blanks:
ab a b a babab a b a bab
Dividing the series into groups of 4 letters or repeating pairs of 'ab':
abab / abab / abab / abab
The pattern forms a repeating sequence of 'abab'.
Thus, the required letters are a a a a.
Therefore, the correct option is (A).