Kidneys in adult frog are

Options

A. Pronephric
B. Metanephric
C. Mesonephric
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the kidneys in adult frogs, which belong to the class Amphibia.

2. **Understand Kidney Types**: In vertebrates, there are three types of kidneys: pronephric, mesonephric, and metanephric. Each type is associated with different stages of development and types of vertebrates.

3. **Determine the Kidney Type in Frogs**: Adult frogs primarily have mesonephric kidneys. This type of kidney is characteristic of amphibians and is the main excretory organ for aquatic vertebrates.

4. **Consider Other Options**:
- Pronephric kidneys are typically found in the early developmental stages of some vertebrates and are not present in adult frogs.
- Metanephric kidneys are found in higher vertebrates such as reptiles, birds, and mammals, but not in adult frogs.
- Therefore, the option stating "All of these" is incorrect.

5. **Conclusion**: Based on the information, the correct answer is that the kidneys in adult frogs are mesonephric.

**Final Answer**: The kidneys in adult frogs are mesonephric (Option 3).

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