Name the body structure concerned with the given functional activity :
Protects the lungs from mechanical injuries.

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the body structure that protects the lungs from mechanical injuries. This indicates we need to identify a protective structure surrounding the lungs.

2. **Identifying Relevant Body Structures**: The lungs are located within the thoracic cavity. To protect the lungs, we need to look for structures that enclose or surround this cavity.

3. **Recognizing the Key Structures**: The primary structures that protect the lungs are the ribs and the sternum. The ribs form a cage-like structure around the thoracic cavity, while the sternum is located at the front of this cavity.

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