Which example from the tempest is the best illustration of the power of language to subjugate people?

a) miranda speaks to fernand's and tells him to take a rest from his work even though his father forbids it

b) gonzalo verbally expresses his utopian ideas to sebastian and antonio

c) prospero teaches his language to caliban and then uses it to communicate with him

d) ariel and caliban make plans to overthrow prospero in their native language so no one can understand them