A deltoid ridge occurs in

Options

A. Radius
B. Ulna
C. Femur
D. Humerus.

Answer

To determine where a deltoid ridge occurs, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the term "deltoid ridge":**
- A deltoid ridge refers to a specific prominence or elevation on a bone that serves as an attachment point for muscles.

2. **Identify the bones in question:**
- The options provided likely include various bones such as the humerus, radius, ulna, and femur.

3. **Focus on the location of the deltoid ridge:**
- The deltoid ridge is associated with the upper arm bone, known as the humerus.

4. **Recognize the function of the deltoid ridge:**
- The deltoid ridge serves as the attachment point for the deltoid muscle, which is responsible for shoulder abduction and other movements of the arm.

5. **Eliminate other options:**
- The radius and ulna are bones of the forearm and do not have a deltoid ridge. The femur is the thigh bone and is not related to the deltoid muscle.

6. **Conclude with the correct answer:**
- Therefore, the deltoid ridge occurs in the humerus.

### Final Answer:
The deltoid ridge occurs in the **humerus**.

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