Assertion : Potometer is used to measure the rate of transpiration.
Reason : It is based on principle that water lost in transpiration is equal to water absorbed.

Options

A. If both Assertion and Reason are true and Reason is correct explanation of Assertions.
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.

Answer

To analyze the given assertion and reason regarding the potometer and transpiration, let's break it down step by step.

### Step 1: Understanding the Assertion
The assertion states that "Potometer is used to measure the rate of transpiration."
- **Explanation**: A potometer is indeed an instrument used to measure the rate at which water is lost from a plant through transpiration. It helps in quantifying the amount of water vapor lost from the leaves, which is an essential aspect of plant physiology.

### Step 2: Understanding the Reason
The reason given is "It is based on the principle that water lost in transpiration is equal to water absorbed."
- **Explanation**: This statement is also correct. The principle behind the potometer is that the amount of water absorbed by the plant roots is equal to the amount of water lost through transpiration. This relationship allows us to measure transpiration indirectly by observing water uptake.

### Step 3: Evaluating the Relationship Between Assertion and Reason
Now, we need to determine if the reason is a correct explanation of the assertion.
- **Explanation**: Since the potometer measures the rate of transpiration based on the principle that water lost is equal to water absorbed, the reason indeed provides a correct explanation for the assertion.

### Conclusion
Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is a correct explanation of the assertion.

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

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