Contour, semi-plume, down-these all are different categories of

Options

A. beaks
B. feathers
C. feet
D. glands

Answer

**Step-by-Step Solution:**

1. **Identify the Categories:** The question asks about the categories of "Contour," "Semi-plume," and "Down." These terms refer specifically to types of feathers found in birds.

2. **Define Contour Feathers:** Contour feathers are the outer feathers that cover a bird's body. They provide protection and help streamline the bird's shape for flight. These feathers also play a role in waterproofing and insulation.

3. **Define Semi-plume Feathers:** Semi-plume feathers are a type of feather that is primarily used for display purposes. They are often found in male birds and are used to attract females during mating displays. These feathers are also referred to as sexual feathers.

4. **Define Down Feathers:** Down feathers are soft and fluffy feathers located beneath the contour feathers. They are primarily responsible for insulation, keeping the bird warm. Down feathers are commonly found in nestlings, which are young birds that require extra warmth.

5. **Conclusion:** Since Contour, Semi-plume, and Down are all types of feathers, the answer to the question is that these are different categories of feathers.

**Final Answer:** Contour, Semi-plume, and Down are different categories of feathers.

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