Bidder's canal occurs in

Options

A. (a) kidney of male frog
B. (b) testis of male frog
C. (c) liver of frog
D. (d) ovaries of female frog

Answer

### Step-by-Step Solution:

1. **Understanding Bidder's Canal**: Bidder's canal is a structure associated with the male reproductive system in frogs. It plays a crucial role in the transportation of sperm.

2. **Identifying the Location**: The canal is specifically found in the kidneys of male frogs. It is not present in female frogs.

3. **Function of Bidder's Canal**: The primary function of Bidder's canal is to carry sperm from the testes to the urinogenital tract. This allows both urine and sperm to pass through a single canal.

4. **Analyzing the Options**: The question provides multiple-choice options regarding the location of Bidder's canal:
- A) Kidney of male frog
- B) Testes of male frog
- C) Liver of frog
- D) Ovaries of female frog

5. **Evaluating Each Option**:
- **Option A (Kidney of male frog)**: This is correct as Bidder's canal is located in the kidneys of male frogs.
- **Option B (Testes of male frog)**: This is incorrect; Bidder's canal does not occur in the testes.
- **Option C (Liver of frog)**: This is also incorrect; the liver is part of the digestive system, not the reproductive system.
- **Option D (Ovaries of female frog)**: This is incorrect as Bidder's canal is exclusively present in males.

6. **Conclusion**: Based on the analysis, the correct answer is **Option A: Kidney of male frog**.