19. ________the garbage dump smells terrible, no one lives around there. A. Because of B.Since C.As a result of D. Even though 20. Grace didn’t love nature, ________ she wasn’t happy when her group went camping in a jungle. A. but B. and C. because D. so 21. Thousands of fish were killed ________ a discharge of poisonous chemicals from a nearby factory. A. because B. lead to C. result in D. as a result of 22. A flood_________ when a large amount of water covers the land. A. occurs B. is occurred C. is occurring D. has occurred 23. Could you list some non-point source __________? A. pollution B. pollutants C. polluting D. polluted 24. Families camped out in a City park after their homes_________ by the earthquake. A. have heavily damaged B. had damaged heavily C. were heavily damaged D. are damaged heavily