[A]: The inner most distinct layer of the cortex is called endodermis.
[R]: The cells of endodermis are nonliving and bear casparian strips

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

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

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "the innermost distinct layer of the cortex is called endodermis."
- This is correct. The endodermis is indeed the innermost layer of the cortex in plant roots.

2. **Understanding the Reasoning (R)**:
- The reasoning states that "the cells of endodermis are nonliving and bear casparian strips."
- This statement is partially incorrect. While it is true that the endodermis bears Casparian strips, the cells of the endodermis are not nonliving; they are living cells.

3. **Conclusion**:
- Since the assertion (A) is true and the reasoning (R) is false, we can conclude that the correct answer is:
- Assertion is true (A is correct).
- Reason is false (R is incorrect).

### Final Answer:
- The assertion (A) is true, while the reasoning (R) is false.

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