The economic system in which freedom of choice is emphasized is
a. capitalism.

c. socialism.
b. command economy.

d. communism.

a. because the u.s. was the leading with the most technology, economy, etc. also was teamed with other allies witch boosted the economy and materials to improve technology and use it.

geography

this is because warmer climates often don't get people sick from the flu and regions where it was often colder more people received the flu. hope this if you need more reasoning i am here to