Question

question 12
which of the following describes a natural source of air pollution?
oil refineries on the gulf coast release benzene and other volatile organic compounds into the atmosphere.
the diesel exhaust from idling school buses is a concern for some parents.
during their vacation, jim and his family drove their car through several national parks.
a dust storm in 1983 dumped 1,000 lb of topsoil onto the city of melbourne, australia.

Explanation:

Oil refineries, school - bus exhaust, and car emissions are human - caused sources of air pollution. A dust storm is a natural phenomenon that can carry particles and cause air pollution.

Answer:

A dust storm in 1983 dumped 1,000 lb of topsoil onto the city of Melbourne, Australia.