A. Fortunately, awareness of the problem of urban heat islands is encouraging new practices designed to make life in cities better for all.

Question: "(31) Many people are working to make this goal a reality." Which sentence should replace sentence 31 to bring this paper to a more effective conclusion? A.Fortunately, awareness of the problem of urban heat islands is encouraging new practices designed to make life in cities better for all. B.Obviously, it is important that we do our part to safeguard our cities and to make them desirable places to live and work. C.In response, city inhabitants are caring for more and more trees around and throughout urban areas. D.Given these facts, it is likely that urban heat islands are going to be part of our world for many years to come.