A new golf course is built next to a river. Over the past several months, the nitrate levels of the water in the river have been increasing. Which best explains the cause of the increasing nitrate levels?Immersive Reader (1 Point) increased growth of algae decreased biodiversity runoff from fertilizer

The commonest source by which nitrates find its way into different water bodies is through runoff from fertilizer applied to different farmlands.

Nitrates represent a very important class of plant nutrients which are highly essential for plant growth. Usually, nitrates enter into water bodies via different sources.

The commonest source by which nitrates find its way into different water bodies is through runoff from fertilizer applied to different farmlands.

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The answer is "runoff from fertilizer".

Explanation:

The fertilizer is any natural or synthetic material, which is applied with soil or tissue of plant species and provides one or more plant foods, which are necessary for plant growth.  

Due to the high durability and excessive irrigation use, nitrate fertilizers, which provide high solubility, as well as the nitrate ion throughout the finishes the product and readily drained away, that's why the given choice is correct.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: