Pygostyle is

Options

A. Largest bone in frog
B. bone present in bird's tail for supporting oil glands
C. hind part of snakes
D. tip of vertebral column of fishes

Answer

**Step-by-Step Solution:**

1. **Definition of Pygostyle**: The pygostyle is a specific anatomical structure found in birds. It is a triangular plate-like structure that is formed from the fusion of several caudal (tail) vertebrae.

2. **Function of Pygostyle**: The primary function of the pygostyle is to support the tail feathers of birds. This structure provides a stable base for the attachment of the feathers, which are crucial for flight and balance.

3. **Presence in Animals**: The pygostyle is unique to birds and is not found in other vertebrates such as frogs, snakes, or fishes. This distinguishes birds from other classes of animals in the phylum Chordata.

4. **Conclusion**: Based on the information, the pygostyle is specifically associated with birds and serves an important role in their anatomy related to flight.

**Final Answer**: Pygostyle is a triangular plate-like structure formed from fused caudal vertebrae, found only in birds, which supports their tail feathers.

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