Choose the correct answer :
In a food chain, the total amount of living material is depicted by :

Options

A. Pyramid of biomass
B. Trophic levels
C. Pyramid of number
D. Pyramid of energy

Answer

To solve the question "In a food chain, the total amount of living material is depicted by:", we need to understand the concepts related to food chains and the different ways to represent living material.

### Step-by-Step Solution:

1. **Understanding Food Chains**: A food chain represents the flow of energy and nutrients through different levels of organisms in an ecosystem. Each level is known as a trophic level.

2. **Identifying the Options**:
- **A. Pyramid of Biomass**: This represents the total mass of living material at each trophic level in a food chain.
- **B. Trophic Level**: This refers to the position an organism occupies in a food chain (e.g., producer, primary consumer, etc.), but does not quantify the total living material.
- **C. Pyramid of Number**: This shows the number of individual organisms at each trophic level, not the total biomass.
- **D. Energy**: This refers to the energy flow through the food chain, usually measured in calories, but does not represent the total living material.

3. **Analyzing the Options**:
- The question specifically asks for the total amount of living material, which relates to the weight or biomass of the organisms.
- The Pyramid of Biomass directly represents the total mass of living organisms at each trophic level.

4. **Conclusion**: Based on the analysis, the correct answer is **A. Pyramid of Biomass**.

### Final Answer:
**A. Pyramid of Biomass**