Why does the author mention both Boston and Chicago A: To demonstrate positive and negative effects of growth. B: To exemplify cities with and without mass transportation. C: To show mass transportation changed many cities. D: To contrast their rate of growt

According to the passage, what should be understood by governments（） A: The link between the environment and the economy is not serious enough. B: The two issues of poverty reduction and the environment have often been connected C: Environmental collapse is a result of economic development D: Environmental collapse is affecting the possibility for growt