Assertion : In change of state from solid to liquid the temperature decreases untill the entire amount of the solid subtance melts.
Reason : The phenomenon of refreezing is called melting

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true and reason is not the correct explanation of assertion.
C. If assertion is true and reason is false.
D. If both assertion and reason are false.

Explanation

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

**Step 1: Analyze the Assertion**
- The assertion states: "In change of state from solid to liquid the temperature decreases until the entire amount of the solid substance melts."
- When a solid melts into a liquid, the temperature remains constant during the phase change. This is because the heat energy supplied is used to break the bonds between the molecules rather than increasing the temperature. Therefore, the assertion is **incorrect**.

**Step 2: Analyze the Reason**
- The reason states: "The phenomenon of refreezing is called melting."
- Refreezing refers to the process of a liquid turning back into a solid, which is the opposite of melting. Melting is the process of a solid turning into a liquid. Therefore, this statement is also **incorrect**.

**Step 3: Conclusion**
- Since both the assertion and reason are incorrect, we conclude that the correct option is that both the assertion and reason are false.

**Final Answer: Both assertion and reason are false.**

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