`10%` law of energy transfer in food chain was given by:

Options

A. Stanley
B. Tranley
C. Lindeman
D. Weismann

Answer

To answer the question regarding who proposed the "10% law of energy transfer" in the food chain, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Food Chain**:
- A food chain consists of different trophic levels, starting with producers (like plants) that capture energy from sunlight.

2. **Energy Transfer in Trophic Levels**:
- When energy is transferred from one trophic level to the next, not all of it is passed on. A significant portion of energy is lost, primarily as heat.

3. **The 10% Rule**:
- The "10% law" states that, on average, only about 10% of the energy from one trophic level is transferred to the next level. For example, if a plant (producer) has 1000 joules of energy, only about 100 joules will be available to the herbivore (primary consumer) that eats it.

4. **Identifying the Scientist**:
- The scientist who formulated this law is Lindemann. He studied energy flow in ecosystems and established the principle that energy transfer between trophic levels is inefficient, with only a fraction being passed on.

5. **Eliminating Incorrect Options**:
- Other names mentioned, such as Stanley and Trelay, are not associated with this law. Therefore, they can be ruled out.

6. **Conclusion**:
- The correct answer to the question is that the "10% law of energy transfer in the food chain" was given by Lindemann.

### Final Answer:
The 10% law of energy transfer in the food chain was given by **Lindemann**.

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