Official 53 Lec 3
Question 1 of 6
What is the lecture mainly about?

A.

The difference between point source and nonpoint source pollution

B.

The source and treatment of a serious type of pollution affecting the Chesapeake Bay

C.

The causes for the large decrease in algae in the Chesapeake Bay

D.

The development of farming methods during the past century

正确答案:B

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