Which of the Following Most Accurately Describes the Process by Which

Which of the following most accurately describes the process by which a dead zone occurs?

A) Increased nutrients lead to increased growth of algae and plants.When these organisms die,decomposers use oxygen in the water to break down the dead organisms.Fish and other marine organisms are thus robbed of the oxygen they need.
B) Overharvesting and poor fishing techniques create areas devoid of life within the ocean.
C) Nutrient runoff leads to increased growth of aquatic algae and plants,which remove oxygen from water in order to photosynthesize.Fish and other marine organisms are thus robbed of the oxygen they need.
D) Fertilizers and pesticides are carried from cities and farmland to the oceans,where these pollutants kill fish and other marine organisms,creating a zone devoid of life near shore.