Answer the following question given this paragraph: 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. Q: What do you call the substance in a cooling system that has a low boiling point and changes between liquid and gaseous states? Choices: - byproduct - emission - coolant - refrigerant A:
Answer:
refrigerant