A High School Student Visiting Lake Erie Reads a Sign

A high school student visiting Lake Erie reads a sign indicating that it is unsafe to swim at a beach because of a toxin called microcystin.The student does some research and finds the following relationship between fertilizer,algae,heterotrophic bacteria,and fish: fertilizer runoff causes

A) algal blooms, which lead to an increase in heterotrophic bacteria and a decrease in fish.
B) increases in heterotrophic bacteria, which leads to an increase in algal blooms and a decrease in fish.
C) increases in fish populations, which leads to decreases in heterotrophic bacteria and algae populations.
D) algal blooms, which lead to a decrease in heterotrophic bacteria and an increase in fish.