Assertion: Gymnosperms are first completely successul land plants.
Reason: In gymnosperms secondary growth is present.

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

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Gymnosperms are the first completely successful land plants." This is true because gymnosperms, which include conifers, were among the first plants to develop seeds, allowing them to thrive in terrestrial environments.

2. **Understanding the Reason**: The reason provided is "In gymnosperms secondary growth is present." This statement is also true. Secondary growth refers to the increase in thickness or girth of the plant, which is characteristic of gymnosperms.

3. **Evaluating the Relationship**: While both the assertion and reason are true, the reason does not directly explain why gymnosperms are considered the first completely successful land plants. The success of gymnosperms on land is primarily due to the development of seeds, which provide protection and allow for colonization of new areas.

4. **Conclusion**: Since both the assertion and reason are true, but the reason does not serve as a correct explanation for the assertion, the correct answer is that both are true, but the reason is not a correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, but the reason is not a correct explanation of the assertion.

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