Assertion:Air sacs are connected to lungs in Class Aves.
Reason: Air sacs supplement respiration in birds.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the assertion and reason question regarding Class Aves, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Assertion and Reason**:
- Assertion: "Air sacs are connected to lungs in Class Aves."
- Reason: "Air sacs supplement respiration in birds."

2. **Evaluate the Assertion**:
- In birds (Class Aves), air sacs are indeed connected to the lungs. This anatomical feature is a well-known characteristic of avian respiratory systems. Therefore, the assertion is **true**.

3. **Evaluate the Reason**:
- The reason states that air sacs supplement respiration in birds. This is also true, as air sacs play a crucial role in the respiratory process of birds by allowing for a continuous flow of air through the lungs, enhancing oxygen exchange. Thus, the reason is **true**.

4. **Determine the Relationship Between Assertion and Reason**:
- Since both the assertion and reason are true, we need to check if the reason correctly explains the assertion. The reason does explain the assertion because air sacs are indeed connected to the lungs and they do supplement respiration.

5. **Select the Correct Option**:
- Based on the evaluation, the correct option is: "If both assertion and reason are true and reason is the correct explanation of the assertion."

### Conclusion:
The correct answer is that both the assertion and reason are true, and the reason correctly explains the assertion.

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