Assertion : Specific heat of any substance remains constant at all temperatures.
Reason : It is given by ` s= 1/m * (dQ)/(dt)` .

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

### Step 1: Understand the Assertion
The assertion states that "Specific heat of any substance remains constant at all temperatures."

- Specific heat capacity (s) is defined as the amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius (or Kelvin).
- However, the specific heat of a substance can change with temperature. For many substances, specific heat varies with temperature due to changes in molecular motion and structure. Therefore, this assertion is **false**.

### Step 2: Understand the Reason
The reason states that "It is given by `s = 1/m * (dQ)/(dt)`."

- This equation represents the definition of specific heat capacity, where:
- \( s \) = specific heat capacity
- \( m \) = mass of the substance
- \( dQ \) = change in heat energy
- \( dt \) = change in temperature
- The equation is indeed correct and reflects how specific heat is calculated. Therefore, this reason is **true**.

### Step 3: Conclusion
Based on the analysis:
- The assertion is **false** because specific heat does not remain constant at all temperatures.
- The reason is **true** as it correctly defines specific heat capacity.

### Final Answer
Thus, the correct conclusion is that the assertion is false and the reason is true. If options are provided, the correct choice would be the one stating that the assertion is incorrect and the reason is correct.

---