Answer:
C. Stewart is bored.
Explanation:
The word "implicit" means an implied or suggested action and not openly stated. In other words, we can say "implicit" refers to something that is assumed and not directly stated.
In the given passage about Stewart's behavior, the speaker tells us directly that "Stewart is in class, ... his backpack slung over his shoulder and his foot tapping ...", which are all explicit statements. The only thing that is left to assume is that Stewart is bored, which is not openly stated.
Thus, the correct answer is option C.
