The study of the structure an behaviour of the physical and natural environment by oberseving through scientficic instruments and through experiments.
Caliban realized that stephano and trinculo aren't smart because they were drunk and obviously drunkards can't even bothered to do anything, and they were not even listening or taking interest when he was talking about the plan to kill Prospero. Soon caliban realized that they were just drunken idiots he was telling his plans to.
D, because when you have two nouns, the verb you should use goes for the noun closest to the verb.