Answer: A. Prospero
Step-by-step explanation:
Prospero is a white magician and the rightful Duke of Milan. His occupation with his magic and books made him neglect his state duties, and he was forced to flee Milan.
Prospero arrives on an enchanted island and enslaves Caliban, a creature that tries to sexually assault his daughter. As Caliban is the only real native of the island, the relationship between Prospero and him perfectly resembles the relationship between the colonizer and the colonized. Prospero captures Caliban in a cave, and forces him to carry the wood and perform other tasks for him. He tries to civilize Caliban, but fails in his attempt. Caliban does learn the language, but his behavior remains the same - he curses, plots against Prospero with Stephano and Trinculo, etc.