Question

what determines whether a benthic zone in a lake will sustain photosynthesis?
a. how deep the lake is
b. how wide the lake is
c. how much it rains near the lake
d. how many plants are near the lake

Explanation:

Photosynthesis requires light. In a lake, the benthic zone is the bottom - most zone. If the lake is too deep, light will not be able to penetrate to the benthic zone. Thus, the depth of the lake determines if there is enough light for photosynthesis in the benthic zone. Width of the lake (B) affects surface - area related factors but not light penetration to the benthic zone. Rainfall (C) and number of plants near the lake (D) do not directly impact light availability in the benthic zone for photosynthesis.

Answer:

A. How deep the lake is