Which is the reason for highest biomass in aquatic ecosystem-

Options

A. Nanoplankton, blue green algae, green algae
B. Sea grass and slime molds
C. Benthoic and brown algae
D. Diatoms

Answer

**Step-by-Step Solution:**

1. **Understanding Biomass in Aquatic Ecosystems:**
- Biomass refers to the total mass of living organisms in a given area or volume. In aquatic ecosystems, biomass is crucial as it indicates the productivity and health of the ecosystem.

2. **Identifying Key Organisms:**
- The question provides several options that include different types of organisms such as nanoplankton, blue-green algae, green algae, seagrass, slime molds, benthic organisms, brown algae, and diatoms.

3. **Analyzing the Options:**
- Option A includes nanoplankton and various algae.
- Option B includes seagrass and slime molds.
- Option C includes benthic organisms and brown algae.
- Option D includes diatoms.

4. **Determining the Role of Benthic and Brown Algae:**
- Benthic algae cover hard bottoms in aquatic environments and can extend down to 40 meters. They are significant as they provide food and energy for various aquatic organisms.
- Brown algae also play a vital role in the ecosystem as they act as decomposers and are a food source for many marine animals.

5. **Conclusion:**
- Based on the roles of benthic and brown algae in providing food and energy, as well as their ecological contributions, it can be concluded that they are the primary contributors to the highest biomass in aquatic ecosystems.

6. **Final Answer:**
- The correct answer is **Option C: benthic and brown algae**.

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