Assertion: In the dicot root the vascualr cambium is completely secondary in roigin
Reason: Vascular cambium originates from the tissue located just below the phloem bundles a portion of pericycle tissue above the protoxylem forming a complete and contiuous wavy ring, which later becomes circular

Explanation

To solve the question regarding the assertion and reason about the vascular cambium in dicot roots, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "In the dicot root, the vascular cambium is completely secondary in origin."
- In dicot roots, the vascular cambium does indeed arise from permanent tissues, specifically from the pericycle and adjacent tissues. Therefore, this assertion is **true**.

2. **Understanding the Reason**:
- The reason provided states that "Vascular cambium originates from the tissue located just below the phloem bundles, a portion of pericycle tissue above the protoxylem forming a complete and continuous wavy ring, which later becomes circular."
- This statement accurately describes the origin of the vascular cambium. It forms from the pericycle and the tissues surrounding the protoxylem and phloem, creating a continuous ring. Thus, this reason is also **true**.

3. **Connecting Assertion and Reason**:
- Since both the assertion and reason are true, we need to determine if the reason correctly explains the assertion.
- The reason explains how the vascular cambium is formed and supports the assertion that it is secondary in origin. Therefore, the reason is indeed the correct explanation of the assertion.

4. **Conclusion**:
- Both the assertion and reason are true, and the reason is the correct explanation of the assertion. Thus, the correct answer is that both statements are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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