What term is used to describe the healthiest lake?

Eutrophic lakes

Explanation:

Eutrophic lakes are the lakes which are in high nutrient content. The high nutrient content supports the large diversity of aquatic plants, algae and aquatic animals. The substrate of the lake is soft and muddy. This provides the suitable environment for the survival of the organisms. The organisms are generally tolerant to the low oxygen and warm temperatures.

On the basis of the above description, eutrophic lakes can be a term used to describe the healthiest lake.

i believe the answer is a or 1