Assertion: Vascular bundles are conjoint, collateral and closed in dicot stem
Reason: vascular bundles are conjoint,collateral and open in monocot stem.

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 analyze the assertion and reason provided in the question, we can break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Vascular bundles are conjoint, collateral, and closed in dicot stem."
- In dicot stems, vascular bundles consist of xylem (inner side) and phloem (outer side), with a cambium layer between them.
- Since both xylem and phloem are present in the same bundle, they are termed "conjoint."
- Because they are arranged on the same radius, they are also "collateral."
- However, the presence of cambium indicates that these bundles are "open," not "closed." Therefore, the assertion is **incorrect**.

2. **Understanding the Reason**:
- The reason states that "Vascular bundles are conjoint, collateral, and open in monocot stem."
- In monocot stems, vascular bundles also consist of xylem and phloem, which are conjoint and collateral.
- However, in monocots, the cambium is absent, which means that the vascular bundles are considered "closed."
- Thus, the reason is also **incorrect**.

3. **Conclusion**:
- Since both the assertion and the reason are incorrect, the correct answer to the question is that both the assertion and reason are false.

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

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