Answer:
The correct answer is A. Caliban is controlled by physical torture, while Ariel is kept under control with mental manipulation.
Step-by-step explanation:
Caliban is physically abused and threatened by Prospero in order to keep him as a slave. He discusses so when he plots with Stephano to kill Prospero. On the other hand, Ariel is kept under control through mental manipulation or rather through emotional blackmail: Prospero keeps Ariel enslaved as a repayment of a favour.