单选题
编号：2455525
1. Which of the following is true?
- A.Enwave ' s system is said to work only in cities located near the Great Lakes.
- B.The water deep in Lake Ontario always remains at the same temperature.
- C.Experts warn that the use of CFCs in Enwave' s system will add to global warming.
- D.Toronto is now searching for new natural sources of water to use in its water supply.