Bidder's canal is found in 

Options

A. testes of frog
B. ovary of mammal
C. kidney of frog
D. kidney of mammal

Answer

**Step-by-Step Solution:**

1. **Understanding Bidder's Canal**: Bidder's canal is a specific anatomical structure associated with the reproductive system of male frogs. It is important to know what Bidder's canal is and where it is located.

2. **Identifying the Options**: The question provides four options:
- Testes of frog
- Ovaries of mammal
- Kidney of frog
- Kidney of mammal

3. **Eliminating Incorrect Options**: Since Bidder's canal is known to be present in frogs, we can eliminate any options that mention mammals. Therefore, we can eliminate:
- Ovaries of mammal (Option 2)
- Kidney of mammal (Option 4)

4. **Focusing on Frogs**: Now we are left with two options related to frogs:
- Testes of frog (Option 1)
- Kidney of frog (Option 3)

5. **Locating Bidder's Canal**: Bidder's canal is not located in the testes but is found within the kidney of male frogs. It serves to transport sperm from the testes.

6. **Final Answer**: Based on the information, the correct answer is **Kidney of frog (Option 3)**.

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