Choices:
i. The bending of a ray of light;
ii. decreasing liquid;
iii. reducing heat energy;
iv. Warm air moving into cold air;
v. movement of tectonic plates;
vi. keeping current temperature;
vii. adding more heat;
viii. evaporation;

You are presented with the quiz "What turns a liquid into a solid?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "freezing means changing from a liquid into a solid by reducing heat energy" and "liquid water holds a huge amount of heat energy and resists changes of state to solid or gas". So, what's the best answer to the question?
Answer:
iii.