Assertion: A glass of water is filled at `4^@ C`. Water will overflow, if temperature is increased or decreased. (Ignore expansion of glass).
Reason: Density of water is minimum at `4^@ C`.

Options

A. If both Assertion and Reason are true and the reason is correct explanation of the Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true, but the Reason is false.
D. If Assertion is false but the Reason is true.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that a glass of water filled at 4°C will overflow if the temperature is increased or decreased.

**Explanation**:
At 4°C, water has its maximum density. If the temperature is increased or decreased from this point, the density of water will decrease. Since the mass of water remains constant, a decrease in density will lead to an increase in volume (using the formula \( V = \frac{m}{\rho} \)). Therefore, the water will overflow when the temperature is changed.

### Step 2: Understand the Reason
The reason states that the density of water is minimum at 4°C.

**Explanation**:
This statement is incorrect. The density of water is actually maximum at 4°C. As the temperature increases or decreases from this point, the density decreases. Therefore, the reason provided is false.

### Step 3: Conclusion
Based on the analysis:
- The assertion is true because the water will overflow when the temperature is changed from 4°C.
- The reason is false because the density of water is not minimum at 4°C; it is maximum.

### Final Answer
Thus, the assertion is true, and the reason is false. The correct option is C.

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