Athick, black liquid formed from the buried remains of microscopic marine organisms is
a.
gangue
c.
alcohol
b.
oil
d.
none of the above

b.  oil

Explanation:

An oil is a thick, black liquid formed from the buried remains of microscopic marine organisms. The type of oil includes petroleum, gasoline and others. These are formed by the decomposition of the organic matter generated after the death of the living organisms by the soil microbes. The matter remains underground until get fully decayed. It takes around millions of years for the underground generation of the oils. These oils are called as fossilized oils.

c should be the answer