Pick the odd one out.
Femur, humerus, tibia, fibula.

Explanation

To solve the question "Pick the odd one out: Femur, Humerus, Tibia, Fibula," we can follow these steps:

### Step 1: Identify the Bones
- **Femur**: This is the longest bone in the human body and is located in the thigh.
- **Humerus**: This bone is found in the upper arm.
- **Tibia**: This is one of the two bones in the lower leg, specifically the larger one.
- **Fibula**: This is the other bone in the lower leg, which is smaller than the tibia.

...