Look back into the passage and discuss what that test entail.
Answer : repetitious
The question above is an example of an analogy. An analogy is one way of comparing things based on its structure. The first pair sullen and moody shows a synonymous relationship because the synonym of sullen is moody therefore, the next pair should be in a synonymous relationship also. It can be concluded that monotonous is to repetitious because the synonym of monotonous is repetitious. It can also mean dull, tedious or the one that lacks variety.
so "higher education", can keep students, like me, paying up the nose for classes you academically don't need to take..seriously tho, the brain remembers bits n pieces of info. your brain may remember the process of solving the issue.