Correct Option: C

An interesting property of matter is that its temperature remains constant during a phase change, assuming its surrounding pressure is constant. A liquid changes into gaseous state at a constant temperature called its boiling point. For example, when water is converted into vapors (gaseous state) at 100°C and so 100°C is its boiling point. The temperature remains constant at 100°C. The temperature of water increases only after all the water is evaporated. Likewise, once the temperature of a liquid is lowered to its freezing point, the temperature does not decrease until all the liquid has changed its phase to become a solid.