In The Tempest, why does Ariel do as Prospero orders him?

A.
Prospero is Ariel's father, and Ariel's misdeeds are the reason that the family was exiled to the island.

B.
Prospero freed Ariel from the evil witch Sycorax, who had imprisoned Ariel in a pine tree for 12 years.

C.
Ariel wishes to marry Miranda, so he will do whatever it takes to impress and please her father, Prospero.

D.
Ariel knows that Prospero intends to get revenge on those who have wronged both of them, so he is eager to help.