Hollow horns occur in

Options

A. Deer
B. Giraffe
C. Buffalo
D. All the above .

Answer

To answer the question "Hollow horns occur in," we will analyze the options provided and determine which animal possesses hollow horns.

### Step-by-Step Solution:

1. **Understanding Hollow Horns**:
- Hollow horns are permanent structures that have a core filled with air. They are typically found in certain species of mammals.

2. **Evaluating the Options**:
- **Option 1: Deer**:
- Deer have deciduous antlers, which means they shed them annually. Therefore, they do not have hollow horns.
- **Option 2: Giraffe**:
- Giraffes do not possess true horns. Instead, they have ossicones, which are made of ossified cartilage and are covered with skin. Hence, they do not have hollow horns.
- **Option 3: Buffalo**:
- Buffalos have hollow horns. These horns are permanent and have air spaces due to the extension of the frontal sinuses into them. This is characteristic of certain bovines.
- **Option 4: All of the above**:
- Since neither deer nor giraffes have hollow horns, this option is incorrect.

3. **Conclusion**:
- After evaluating all options, the correct answer is **Option 3: Buffalo**, as they are the only ones listed that possess hollow horns.

### Final Answer:
Hollow horns occur in **Buffalo**.

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