Assertion (A) Thallus is non vascular somatic body.
Reason (R ) It does not show differentiation of stem, leaves and roots.

Options

A. Both Assertion and Reason are correct, and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
C. Assertion is correct, but Reason is incorrect
D. Assertion is incorrect, but Reason is correct

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion (A):**
- The assertion states that "Thallus is a non-vascular somatic body."
- This means that thallus, which is found in organisms like algae, fungi, and liverworts, does not have vascular tissues (xylem and phloem) that are typically present in higher plants.

2. **Understanding the Reason (R):**
- The reason states that "It does not show differentiation of stem, leaves, and roots."
- This indicates that the thallus structure is not divided into distinct organs like stems, leaves, or roots, which is a characteristic of more complex plants.

3. **Evaluating the Assertion:**
- The assertion is true because thallus indeed lacks vascular tissues and is a simple body form found in non-vascular plants.

4. **Evaluating the Reason:**
- The reason is also true because thallus does not exhibit differentiation into specialized structures like stems, leaves, or roots.

5. **Conclusion:**
- Since both the assertion and the reason are true, and the reason correctly explains the assertion, we can conclude that both statements are correct.

**Final Answer:**
Both the Assertion (A) and Reason (R) are correct, and the reason supports the assertion.

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