Pick the odd one out.
Skull, vertebral column, sternum, limbs.

Explanation

To solve the question "Pick the odd one out" from the options: Skull, vertebral column, sternum, and limbs, follow these steps:

### Step 1: Identify the Categories
- **Skull**: Part of the axial skeleton, located in the head.
- **Vertebral Column**: Also part of the axial skeleton, located below the skull, forming the backbone.
- **Sternum**: Another component of the axial skeleton, located in the chest area.
- **Limbs**: Comprise the arms and legs, which are part of the appendicular skeleton.

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