Which of the following best characterizes the benthic zone of a lake?

• A. It is the zone with the highest concentration of phytoplankton.
• B. It is the bottom layer of the lake, often rich in nutrients.
• C. It is the region where water temperature is the warmest.
• D. It is the area with the highest light penetration.

Answer: (B)

Verified step by step guidance

1. Understand the definition of the benthic zone: The benthic zone is the ecological region at the lowest level of a body of water, such as a lake, including the sediment surface and some sub-surface layers.
2. Consider the characteristics of the benthic zone: It is typically rich in nutrients due to the accumulation of organic matter and sediments.
3. Evaluate the options given: The benthic zone is not characterized by high concentrations of phytoplankton, warm water temperatures, or high light penetration.
4. Identify the correct characterization: The benthic zone is best described as the bottom layer of the lake, often rich in nutrients.
5. Conclude by understanding why the other options are incorrect: Phytoplankton are more abundant in the photic zone where light penetration is highest, and warmer temperatures are usually found in the upper layers of the lake.