A pygostyle bone is the :-

Options

A. Part of pelvic girdle of Rabbit
B. Last few caudal vertebrae in birds
C. Part of skull of Frog
D. Last caudal vertebrae of Frog

Answer

To answer the question "A pygostyle bone is the:", we will analyze the options provided and determine the correct answer step by step.

### Step-by-Step Solution:

1. **Understand the Definition of Pygostyle**:
- The pygostyle is a bone found in birds. It is formed from the fusion of the last few caudal (tail) vertebrae.

2. **Examine the Options**:
- **Option A**: Part of the pelvic girdle of rabbit.
- This option is incorrect because the pygostyle is not related to the pelvic girdle of any animal, including rabbits.

- **Option B**: Last few caudal vertebrae in birds.
- This option is correct. The pygostyle is indeed formed by the fusion of the last few caudal vertebrae in birds and forms the posterior end of their vertebral column.

- **Option C**: Part of the skull of frog.
- This option is incorrect as the pygostyle has no relation to the skull of frogs.

- **Option D**: Last caudal vertebrae of frog.
- This option is also incorrect. The pygostyle pertains specifically to birds, not frogs.

3. **Conclusion**:
- After analyzing all the options, we conclude that the correct answer is **Option B: Last few caudal vertebrae in birds**.

### Final Answer:
A pygostyle bone is the last few caudal vertebrae in birds.

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