GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - TQ77VK51BS2TRNNKJ

Which of the following is most similar to the role played by marine algae in the global climate control system proposed by Lovelock? A. A fan that continually replaces stale air in a room with fresh air from outside. B. A thermostat that automatically controls an air-conditioning system. C. An insulating blanket that retains heat. D. A filter used to purify water. E. A dehumidifier that constantly removes moisture from the air in a room.