The correct answer is A. G, H, I.
The first two letters of each pair are in alphabetical order, starting with A and B. The third letter of each pair is one letter after the second letter, starting with N and O. Therefore, the next three letters in the sequence are G, H, and I.
Option B is incorrect because J comes after H in the alphabet, not after I. Option C is incorrect because Q does not follow the pattern of the other letters in the sequence. Option D is incorrect because J, K, and L do not follow the pattern of the other letters in the sequence.