Which of the following does not constitute appendicular skeleton ?

Options

A. Coxal bone
B. Scapula
C. Humerus
D. Sternum

Answer

To determine which of the following does not constitute the appendicular skeleton, we need to understand the components of both the axial and appendicular skeletons.

### Step-by-Step Solution:

1. **Identify the Types of Skeletons**:
- The human skeleton is divided into two main parts: the axial skeleton and the appendicular skeleton.
- The axial skeleton consists of 80 bones, including those of the head, neck, back, and chest.
- The appendicular skeleton consists of 126 bones, which include the bones of the upper limbs, lower limbs, the pelvic girdle, and the pectoral girdle.

2. **Analyze the Options**:
- **Option A: Coxal Bone**: This is part of the pelvic girdle and is included in the appendicular skeleton.
- **Option B: Scapula**: This is part of the pectoral girdle and is also included in the appendicular skeleton.
- **Option C: Humerus**: This is a bone of the upper limb and is part of the appendicular skeleton.
- **Option D: Sternum**: This is a bone located in the chest and is part of the axial skeleton.

3. **Determine the Correct Answer**:
- Since the sternum is the only option that is part of the axial skeleton and not the appendicular skeleton, the correct answer is **Option D: Sternum**.

### Final Answer:
The structure that does not constitute the appendicular skeleton is the **sternum**.

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