Task: Class Definition Understanding (ontology: Earth_Environment/EnvironmentOntology)

Which of the following definitions best describes 'warming of a gas'?

A. An erosional process in which bedrock is converted from its solid form into a solute by the action of some solvent.
B. A research facility consisting of instruments that measure the properties of the oceans over time. Usually of at least approximately fixed location.
C. A process of warming a fluid during which the thermal energy in a volume of gas increases.
D. A process of warming a fluid which includes a volume of liquid as a participant.

Answer: A process of warming a fluid during which the thermal energy in a volume of gas increases.