One reason streams become polluted is stormwater runoff. When rain or melted snow runs off, it carries trash from sidewalks and streets with it. These pollutants flow into storm sewers or directly into a lake, stream, or river. Then, bacteria from the trash spread to create health hazards. The trash itself can choke and suffocate ducks, fish, turtles, and birds. Used motor oil, paint, and insecticides can poison fish. 2. According to this passage, which of the following is caused by stormwater runoff?