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 need to analyze the options provided and determine which one correctly describes the pygostyle bone.

### Step-by-Step Solution:

1. **Understanding the Term "Pygostyle":**
- The pygostyle is a specific anatomical structure found in certain animals, particularly birds. It is important to know its definition and location.

2. **Analyzing the Options:**
- **Option A:** Part of pelvic girdle of rabbit
- **Option B:** Last few caudal vertebrae in birds
- **Option C:** Part of skull of frog
- **Option D:** Last caudal vertebrae of frog

3. **Evaluating Each Option:**
- **Option A:** The pygostyle is not found in rabbits and does not relate to the pelvic girdle.
- **Option B:** The pygostyle is indeed formed by the fusion of the last few caudal vertebrae in birds, making this option a strong candidate.
- **Option C:** The pygostyle is not part of the skull of frogs; this option is incorrect.
- **Option D:** The pygostyle is not related to the caudal vertebrae of frogs either.

4. **Conclusion:**
- Based on the definitions and evaluations, the correct answer is **Option B: Last few caudal vertebrae in birds**. The pygostyle is specifically the bone at the posterior end of the spinal column in birds, formed by the fusion of several caudal vertebrae.

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

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