ACT, EGG, INK, ______ What is the next term in the series?

Question: ACT, EGG, INK, ______ What is the next term in the series?

Solution:
In the English alphabet, there are five vowels (A, E, I, O, U).
Here, 1st position starts with A, 2nd position starts with E, 3rd position starts with I,

∴ the 4th position will start with O. So, the correct answer is OLD.