The functional kidney of frog tadpole is

Options

A. archinephros
B. pronephros
C. mesonephros
D. metanephros

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the functional kidney of a frog tadpole. We need to identify which type of kidney is operational during this stage of development.

2. **Identifying the Options**: The options provided are:
- Arachinephros
- Pronephros
- Mesonephros
- Metanephros

3. **Analyzing Each Option**:
- **Arachinephros**: This is an ancestral vertebrate kidney found in hagfish larvae. It is not relevant to frog tadpoles.
- **Pronephros**: This is the most primitive type of kidney and is the first stage of kidney development in vertebrates. It is functional in frog tadpoles.
- **Mesonephros**: This kidney type is present in adult fish and amphibians. It replaces the pronephros as the functional kidney in adult frogs.
- **Metanephros**: This is the embryonic kidney in vertebrates and is not the functional kidney in frog tadpoles.

4. **Conclusion**: Based on the analysis, the functional kidney of a frog tadpole is the **Pronephros**.

5. **Final Answer**: The correct answer is **Pronephros**.

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