Assertion : Living organisms are self replicating, evolving and self regulating unit.
Reason : Living organisms are capable of responding to external stimuli.

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 correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Living organisms are self-replicating, evolving, and self-regulating units."
- **Self-replicating** means that living organisms can reproduce and create offspring similar to themselves.
- **Evolving** refers to the ability of living organisms to change over generations, adapting to their environment.
- **Self-regulating** indicates that living organisms can maintain internal stability and regulate their own processes.

2. **Understanding the Reason**:
- The reason states that "Living organisms are capable of responding to external stimuli."
- This means that living organisms can react to changes in their environment, which is a fundamental characteristic of life.

3. **Evaluating the Truth of the Statements**:
- Both the assertion and the reason are true. Living organisms indeed possess the ability to replicate, evolve, and self-regulate. Additionally, they can respond to external stimuli.

4. **Determining the Relationship**:
- We need to assess whether the reason is a correct explanation of the assertion.
- While both statements are true, the ability to respond to external stimuli (the reason) does not directly explain why living organisms are self-replicating, evolving, and self-regulating (the assertion). They are related characteristics of living organisms, but one does not explain the other.

5. **Conclusion**:
- Therefore, the correct answer is: Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.

### Final Answer:
Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.

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