2. what happends at a oil refinery?

An oil refinery is an industrial plant in which oil is converted into other products like gasoline, diesel, kerosene, among others.

Explanation:

Oil refineries are very important for the oil industry and they are big facilities with several units, tanks and pipes running through the place.

In the oil refineries the crude oil that is not useful is turned into different components that have a variety of uses as fuels.

the answer is the last option or letter d)