Oil formation occurs where millions of years ago there were large oceans. this is because oceans have

A - waves that are constantly moving

B - great numbers of tiny marine animals

C-currents that mix the water throughly

D-deep caverns where no light can reach

Answer: A - waves that are constantly moving

Explanation:

Oil is formed from remains that settles in the ocean over the year, this remains are be acted upon by bacteria in the oceans to form hydrocarbons from where fossil fuel is formed in the ocean floor. This is possible because of the movements of waves in the ocean that allows for mixing of this remain and its movement to ocean floor.