Read the following excerpt from President John F. Kennedy's "We Choose to Go to the Moon" speech. Then, answer the question that follows.

We set sail on this new sea because there is new knowledge to be gained, and new rights to be won, and they must be won and used for the progress of all people.

Which rhetorical device does Kennedy use to support his argument?

a) Antithesis: he is contrasting space with the ocean
b) Figurative language: he is using a metaphor to compare space exploration to a journey at sea
c) Irony: he is saying the opposite of what he means about the ocean
d) Rhetorical question: he issues a statement about the sea in the form of a question

a) Antithesis: he is contrasting space with the ocean