Right ovary is rudimentary in

Options

A. Shark
B. Birds
C. Sphenodon
D. Calotes

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which organism has a rudimentary right ovary. The options provided are shark, birds, sphenodon, and callots.

2. **Defining the Ovary**: The ovary is a female reproductive organ responsible for producing eggs. In some species, one of the ovaries may be non-functional or rudimentary.

3. **Analyzing Each Option**:
- **Shark**: Sharks belong to the class Chondrichthyes and have a pair of functional ovaries. Therefore, this option is incorrect.
- **Birds**: In birds, the right ovary is indeed rudimentary and non-functional, while the left ovary is fully functional. This option is correct.
- **Sphenodon**: This reptile also has a pair of functional ovaries, making this option incorrect.
- **Callots**: As reptiles, callots also possess a pair of functional ovaries, which means this option is incorrect as well.

4. **Conclusion**: The only organism from the options provided that has a rudimentary right ovary is birds. Thus, the correct answer is **birds**.

### Final Answer:
The right ovary is rudimentary in **birds**.

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