One thing people in the united states could do to reduce air pollution is
a. drive their cars more.
b. burn more fossil fuels.
c. use more public transportation.
d. build more factories. select the best answer from the choices provided a b c d

Let's look at all the options:

a. drive their cars more.
-no, this is false.In fact cars increase pollution: so the opposite is true.

b. burn more fossil fuels.
-this is also false, burning  fossil fuels are one of the main reasons for our pollution

c. use more public transportation.
-this is true! using more public transportation will make people use less cars, and cars increase pollution.

d. build more factories.
-this is also false, factories contribute to pollution.