1. The world's population is __________. A. growing slowly B. staying the same C. growing quickly 2. Tokyo has __________ people. A. below 15 million B. around 15 million C. much more than 15 million 3. Problems in big cities affect __________. A. poor people B. people who live in slums C. everyone 4. Some problem that poor people face in cities include __________. A. traffic and air pollution B. healthy problems and stress C. having no home or living in slums 5. When air pollution is bad, people __________. A. only go out at night B. don't go out C. move to smaller cities