4.which of the following could result from an algal bloom in a river?
a. the algae purify the water.
b. the local plants produce flowers early.
c. fish and other aquatic life die off.
d. plant and animal populations increase.
me out

The answer is c. Fish and other aquatic life die off. Algal bloom occurs as the excess of nutrients. Algae use this increased nutrients to enhance their own growth. Soon, a great number of algae is present in the river. All function normally until a great number of algae die and decomposition begins. Oxygen is needed for decomposition and soon it will be depleted from a body of water. This will lead to the death of fish and other aquatic organisms that depend on oxygen.

A, if i am wrong correct me