Assertion (A): The increasing pressure on water decreases its freezing point.
Reason (R ):The density of water is maximum at `273 K`.

Options

A. If both `(A)` and `(R )` are correct, and `(R )` is the correct explanation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is not the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If `(A)` is correct, but `(R )` is correct.

Explanation

To solve the assertion and reason question, we will analyze both statements individually and determine their correctness.

### Step-by-Step Solution:

1. **Analyze the Assertion (A)**:
- The assertion states: "The increasing pressure on water decreases its freezing point."
- This statement is **correct**. According to the principles of physical chemistry, increasing pressure on water does indeed lower its freezing point. This is because higher pressure disrupts the formation of the crystalline structure that water molecules need to arrange themselves into when they freeze.

2. **Analyze the Reason (R)**:
- The reason states: "The density of water is maximum at 273 K."
- This statement is **incorrect**. The maximum density of water occurs at approximately 4°C, which is equivalent to 277 K, not at 273 K. Therefore, this reason does not support the assertion.

3. **Conclusion**:
- Since the assertion is correct and the reason is incorrect, we can conclude that the correct option is:
- **Option 3**: If A is correct, R is incorrect.

### Final Answer:
The correct option is **Option 3**: If A is correct, R is incorrect.

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