If a Public Health Official Was Trying to Reduce the Potential

If a public health official was trying to reduce the potential for human exposure to a "red tide," which of the following actions would they take?

A) place a ban on eating shellfish that were exposed to the dinoflagellate Alexandrium catanella
B) decrease the amount of nutrients that are washed into the aquatic ecosystem
C) ban swimming and other recreational activities in the area
D) All of these actions would help reduce the potential for human exposure to a "red tide."