Assertion: Phloem fibres or bast fibres are made up of collenchymatous cells.
Reason: Phloem fibres are generally found in primary phloem.

Options

A. If both assertion and reason are true and reason is the correct explanantion 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, we will analyze both statements step by step.

### Step 1: Analyze the Assertion
The assertion states: "Phloem fibres or bast fibres are made up of collenchymatous cells."

- **Understanding Phloem Fibres**: Phloem fibres, also known as bast fibres, are a component of the phloem tissue in plants.
- **Cell Type**: Phloem fibres are actually made up of sclerenchymatous cells, not collenchymatous cells. Sclerenchyma cells are characterized by their thick cell walls and provide mechanical support to the plant.

### Step 2: Analyze the Reason
The reason states: "Phloem fibres are generally found in primary phloem."

- **Location of Phloem Fibres**: Phloem fibres are typically found in the secondary phloem, not the primary phloem. The primary phloem is formed during the primary growth of the plant, while secondary phloem is produced during secondary growth.

### Step 3: Conclusion
Both the assertion and the reason are incorrect:
- The assertion is false because phloem fibres are made up of sclerenchymatous cells, not collenchymatous cells.
- The reason is false because phloem fibres are generally found in secondary phloem, not primary phloem.

### Final Answer
Both the assertion and the reason are false.

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