A : The maximum possible error in a reading is taken as least count of the measuring instrument.
R : Error in a measurement cannot be greater than least count of the measuring instrument.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Analyze the Assertion
The assertion states: "The maximum possible error in a reading is taken as the least count of the measuring instrument."

- **Explanation**: The least count of a measuring instrument is defined as the smallest division or the smallest increment that can be measured accurately with that instrument. For example, if we use a meter scale with a least count of 0.1 cm, then the smallest measurement we can reliably read is 0.1 cm. Therefore, the maximum possible error in any measurement taken with this scale can be considered as ±0.1 cm.

### Step 2: Analyze the Reason
The reason states: "Error in a measurement cannot be greater than least count of the measuring instrument."

- **Explanation**: This statement is not entirely accurate. While the least count provides a guideline for the precision of the instrument, it does not account for all types of errors. For instance, human errors can occur during measurement, which may lead to discrepancies greater than the least count. For example, if a person misreads a measurement, the error can exceed the least count, indicating that the statement is false.

### Step 3: Conclusion
Based on the analysis:
- The assertion is true because the maximum possible error in a reading is indeed taken as the least count of the measuring instrument.
- The reason is false because errors in measurement, especially human errors, can exceed the least count.

Thus, the correct answer is that the assertion is true, but the reason is false.

### Final Answer
The correct answer is: Assertion (A) is true, Reason (R) is false.

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