Assertion : Smooth muscles are known as involuntary muscles
Reason : Smooth muscles are controlled by autonomic nervous system.

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 question, we need to analyze the assertion and the reason provided:

### Step-by-Step Solution:

1. **Understand the Assertion**:
- The assertion states that "Smooth muscles are known as involuntary muscles."
- This is true because smooth muscles operate without conscious control, meaning they are involuntary.

2. **Understand the Reason**:
- The reason states that "Smooth muscles are controlled by the autonomic nervous system."
- This is also true as the autonomic nervous system regulates involuntary functions, including the activity of smooth muscles.

3. **Evaluate the Relationship**:
- We need to determine if the reason provided is the correct explanation for the assertion.
- Since smooth muscles are indeed controlled by the autonomic nervous system, this supports the assertion that they are involuntary muscles.

4. **Select the Correct Option**:
- Given that both the assertion and the reason are true, and the reason correctly explains the assertion, the correct answer is:
- **Option 1**: Both assertion and reason are true, and reason is the correct explanation of assertion.

### Final Answer:
The correct option is **1**: Both assertion and reason are true, and reason is the correct explanation of assertion.

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