Nitrogen is used in many plant fertilizers. When it rains, the excess fertilizers run off into streams,
rivers, and eventually are carried to the ocean. Algae in the water feed off of the nitrogen in the
fertilizers. The excess nutrients can cause a huge mat of algae to grow, called an algal bloom.
When the nitrogen is all used up, the algae die and decomposing bacteria begin to consume them. The
bacteria multiply and consume most of the oxygen in the water, causing many of the fish and other
larger organisms in the water to suffocate and die.
How could the problem of algal blooms be solved?

A. Fish should be trained to swim to other parts of a body of water when the oxygen
levels in one area become too low..
B. Antibiotics should be added to the oceans to kill all of the bacteria before they can
consume the dead algae.
C. The government should start a program in which they clean out all the algae from the
lakes and streams before they become a problem,
D. Farmers and gardeners should use other methods to provide crops with the nitrogen
they need