Q: What do you call the substance in a cooling system that has a low boiling point and changes between liquid and gaseous states?


Read this paragraph and choose the correct option from the provided answers:

The key to how a refrigerator or other cooling system works is the refrigerant. A refrigerant is a substance with a low boiling point that changes between liquid and gaseous states as it passes through the refrigerator.

 Choices:

- byproduct

- emission

- coolant

- refrigerant


A:
refrigerant