C.
Biotic mean alive, so we can cut off the first 2 easily. Aquatic birds eat frogs, so that one is safe for now. A decrease in something parasitic usually helps the population, so D is out too. The only one left is C.
Mycorrhizae are associations between fungi and the roots of plants, where the Fungi provides minerals to the plant. It enabled plants and fungi to be the first organisms to invade land successfully 430 million years ago. In most cases the relationship between host plants and the mycorrhizal fungus is mutualistic, or mutually beneficial. The Mycorrhizal fungi come into direct contact with plant roots and with the soil, adding to the plants ability to gather nutrients and water from the soil through the fungus.
The Use of nitrogen fertilizers near the lake is your answer.
Turbidity<span> is the cloudiness or </span>haziness<span> of a </span>fluid<span> caused by large numbers of individual </span>particles<span> that are generally invisible to the </span>naked eye<span>, similar to </span>smoke<span> in </span>air<span>.</span>
