Question

1pt why are phytoplankton usually not found in deep water?

a. the amount of dissolved gas is too low.

b. the salinity is too high.

c. the temperature is too low.

d. there is not enough sunlight.

Explanation:

Phytoplankton perform photosynthesis, which requires sunlight. In deep water, sunlight cannot penetrate sufficiently. Option A: Dissolved gas levels don't primarily limit phytoplankton in deep water. Option B: Salinity isn't the main reason as phytoplankton can exist in various salinity levels. Option C: Temperature alone isn't the key factor; lack of sunlight is more critical for their photosynthetic needs. So the correct answer is D.

Answer:

D. There is not enough sunlight.