Assertion: The cellwall of diatoms is indestructible.
Reason: The cell wall of diatoms is embedded with calcium carbonates.

Options

A. If both assertion and Reason are true and the reason is a correct explanation of the assertion.
B. If both Assertion and 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 and Reason are False.

Answer

To analyze the assertion and reason provided in the question, we will follow these steps:

### Step 1: Understand the Assertion
The assertion states that "The cell wall of diatoms is indestructible."
- Diatoms are a group of microalgae known for their unique cell walls, which are indeed very durable and can withstand various environmental conditions.

### Step 2: Understand the Reason
The reason states that "The cell wall of diatoms is embedded with calcium carbonates."
- This statement is incorrect. The cell walls of diatoms are primarily composed of silica (silicon dioxide), not calcium carbonate.

### Step 3: Evaluate the Truth of the Statements
- The assertion is true because diatom cell walls are indeed indestructible due to their silica composition.
- The reason is false because diatom cell walls are not made of calcium carbonate.

### Step 4: Conclusion
Since the assertion is true and the reason is false, the correct answer to the question is: "Assertion is true, but the reason is false."

### Final Answer
The correct option is: Assertion is true, but the reason is false.

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