Name the body structure concerned with the given functional activity :
Prevents food from entering the trachea during swallowing.

Explanation

**Step-by-Step Solution:**

1. **Identify the Function**: The question asks for a body structure that prevents food from entering the trachea during swallowing. This is an important protective mechanism in the respiratory and digestive systems.

2. **Understand the Role of the Structure**: The structure that performs this function is responsible for covering the trachea when food is being swallowed, ensuring that food does not enter the airway.

3. **Name the Structure**: The body structure that fulfills this role is called the **epiglottis**.

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