(A): Systametic errors are due to a definite cause and can be minimised.
(R): Random errors are due to unknown reasons and can be completely eliminated .

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the correct explanation of (A)
C. (A) is true but (R) is false
D. Both (A) and (R) are false

Answer

To solve the question, we need to analyze the assertion (A) and the reason (R) provided:

**Assertion (A):** Systematic errors are due to a definite cause and can be minimized.
**Reason (R):** Random errors are due to unknown reasons and can be completely eliminated.

### Step-by-Step Solution:

1. **Evaluate the Assertion (A):**
- Systematic errors are indeed caused by identifiable factors, such as calibration errors, measurement biases, or consistent environmental influences.
- These errors can often be minimized through careful experimental design and calibration of instruments.
- Therefore, the assertion (A) is **True**.

2. **Evaluate the Reason (R):**
- Random errors arise from unpredictable fluctuations in measurements, which can be due to various factors such as equipment precision, observer interpretation, or environmental changes.
- While random errors can be reduced by taking multiple measurements and averaging them, they cannot be completely eliminated because they are inherently unpredictable.
- Thus, the reason (R) is **False**.

3. **Conclusion:**
- Since assertion (A) is true and reason (R) is false, the correct option is: **A is true but R is false**.

### Final Answer:
The correct option is: **Option 3: A is true but R is false.**

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