Which of the following enable the united states to open up trade with japan in the mid 1800s

Are these the choices?

a. The U.S sent several diplomats to negotiate arrangements.
b. The U.S sent a flee of modern naval warships that intimidated the Japanese
c. The U.S offered new technologies to Japan in exchange or trading rights
d. The U.S refused to trade with Japan until it modernized its industry.

The answer is Letter B - The U.S sent a flee of modern naval warships that intimidated the Japanese. On July 8, 1853, American Commodore Matthew Perry led his four ships into the harbor at Tokyo Bay.

What are the statements?