Assertion: In dicot stem, the vascular bundles are open.
Reason: Cambium is present between xylem and phloem of vascular bundle in dicot stem.

Options

A. If both Assertion and Reason are true and Reason is the correct explanation 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. Both Assertion and Reason are false.

Answer

To analyze the assertion and reason provided in the question, we will break it down step by step.

### Step 1: Understand the Assertion
The assertion states that "In dicot stem, the vascular bundles are open."

- **Explanation**: In dicot plants, the vascular bundles are considered "open" because they contain a layer of cambium. This cambium allows for secondary growth, meaning that the plant can grow in thickness over time.

### Step 2: Understand the Reason
The reason given is that "Cambium is present between xylem and phloem of vascular bundle in dicot stem."

- **Explanation**: The cambium is a type of meristematic tissue that is responsible for the production of new xylem and phloem cells. In dicot stems, the cambium is located between the xylem (which transports water and minerals) and the phloem (which transports food). This arrangement is what makes the vascular bundles open.

### Step 3: Connect the Assertion and Reason
Now we need to determine if the reason supports the assertion.

- **Analysis**: The presence of cambium between xylem and phloem in dicot stems is indeed the reason why the vascular bundles are classified as open. Therefore, both the assertion and the reason are correct, and the reason correctly explains the assertion.

### Conclusion
Both the assertion and the reason are true, and the reason provides a valid explanation for the assertion.

### Final Answer
- **Assertion**: True
- **Reason**: True
- **Explanation**: The reason explains why the assertion is true.

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