$ Vacuoles help in compartmentisation inside a cell.
! A eukaryotic flagellum is formed of a protein called flagellin.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the assertion and reason question, we need to analyze both statements carefully.

### Step 1: Analyze the Assertion
The assertion states that "vacuoles help in compartmentalization inside a cell."
- Vacuoles are membrane-bound organelles found in eukaryotic cells.
- They play a crucial role in storing substances, maintaining turgor pressure, and separating different biochemical processes within the cell.
- Therefore, the assertion is **correct** because vacuoles do indeed contribute to compartmentalization.

### Step 2: Analyze the Reason
The reason states that "a eukaryotic flagellum is formed of a protein called flagellin."
- This statement is **incorrect**. Eukaryotic flagella are primarily composed of microtubules arranged in a "9+2" structure, not flagellin, which is a protein found in prokaryotic flagella.
- Therefore, the reason is **incorrect**.

### Step 3: Conclusion
- Since the assertion is correct and the reason is incorrect, we can conclude that the correct answer is that the assertion is correct and the reason is wrong.

### Final Answer
The correct answer is: **Assertion is correct and reason is wrong.**

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