The only true skin gland of the bird is

Options

A. Sweat gland
B. Sebaceous gland
C. Uropygial gland
D. Femoral gland

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for the only true skin gland found in birds.

2. **Identifying Glands in Birds:** Birds have very few skin glands compared to mammals. The options provided include sweat glands, sebaceous glands, urophygial glands, and femoral glands.

3. **Evaluating Each Option:**
- **Sweat Glands:** Birds do not have sweat glands like mammals do. This option can be eliminated.
- **Sebaceous Glands:** While sebaceous glands are oil-secreting glands, in birds, the specific gland that serves this function is the uropygial gland. Thus, this option is not the correct answer.
- **Uropygial Glands:** This is the correct answer. The uropygial gland, also known as the preen gland, is bilobed and located below the tail of the bird. It secretes oil that helps maintain the condition of feathers.
- **Femoral Glands:** These are not recognized as true skin glands in birds, so this option can also be eliminated.

4. **Conclusion:** The only true skin gland of the bird is the **uropygial gland**.

**Final Answer:** Uropygial gland.

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