OPT: [I] vibrations of the atoms [II] kinetic energy [III] degrees Celsius [IV] The bending of a ray of light [V] degrees celcius [VI] Evaporation of water [VII] evaporative cooling [VIII] fissures of hot, acidic water

Fact 1: Heating a liquid can be used to identify that liquid 's boiling point. Fact 2: Heat is caused by vibrations of the atoms and molecules of substances. Given the two facts above, to identify that liquid 's boiling point requries?
Answer:
[I]