Assertion :- Cholesterol provides stability on eukaryotic membrane.
Reason:- Cholesterol molecule are more rigid than the phospholipid.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false.

Answer

To solve the question regarding the assertion and reason about cholesterol and eukaryotic membranes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Cholesterol provides stability on eukaryotic membrane."
- **Analysis**: This statement is true. Cholesterol is indeed a crucial component of eukaryotic cell membranes and contributes to their structural integrity and stability.

2. **Understanding the Reason**: The reason provided is "Cholesterol molecules are more rigid than the phospholipid."
- **Analysis**: This statement is also true. Cholesterol has a more rigid structure compared to the flexible phospholipid molecules, which allows it to maintain membrane stability.

3. **Connecting Assertion and Reason**: Now, we need to determine if the reason correctly explains the assertion.
- **Explanation**: Cholesterol does provide stability to the membrane by intercalating between phospholipids. It helps to prevent the membrane from becoming too fluid at high temperatures and too rigid at low temperatures, thus maintaining an optimal level of fluidity.

4. **Conclusion**: Since both the assertion and reason are true, and the reason correctly explains the assertion, we conclude that the correct answer is:
- **Option 1**: Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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

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