Which of the following rules regarding the significant figures and calculations involving them is not correct?

Options

A. The result of an addition or subtraction is reported to the same number of decimal places as present in number with least decimal places.
B. Result of multiplication or division should have same number of significant figures as present in most precise figure.
C. The result of multiplication or division should be rounded off to same number of significant figures as present in least precise figure.
D. The non-significant figures in the measurements are rounded off.

Explanation

To determine which rule regarding significant figures is incorrect, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Significant Figures in Addition/Subtraction**:
- Rule: The result of an addition or subtraction is reported to the same number of decimal places as the number with the least decimal places.
- Example: Adding 1.1 (1 decimal place) and 1.21 (2 decimal places) gives 2.31. Since 1.1 has the least decimal places (1), we round 2.31 to 2.3.
- Conclusion: This rule is **correct**.
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