Which of the following is the use of frog?

Options

A. Legs of frog are used as food
B. Frog is suitable for classroom studies
C. Frogs maintain ecological balance because they serve as an important link of food chain and food web
D. All

Answer

**Step-by-Step Solution:**

1. **Identify the Uses of Frogs**: The question asks for the uses of frogs, so we need to evaluate the options provided.

2. **Evaluate Each Statement**:
- **First Statement**: "Legs of frog are used as food."
- This is true, as frog legs are considered a delicacy in various cultures, particularly in countries like China and Thailand.

- **Second Statement**: "Frog is suitable for classroom studies."
- This is also true. Frogs are commonly used in biology classes for dissection and studying anatomy, making them an important educational tool.

- **Third Statement**: "Frogs maintain ecological balance."
- This statement is correct as well. Frogs play a crucial role in the food chain, consuming insects and being prey for larger animals, thus helping to maintain ecological balance.

3. **Conclusion**: Based on the evaluation of the statements, all three uses of frogs mentioned are valid. Therefore, the correct answer is that frogs are used for food, educational purposes, and maintaining ecological balance.

**Final Answer**: All of the above statements regarding the uses of frogs are correct.

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