【题目】Resources and investment are heavily concentrated in big cities, contributing to the population __________ and the dilemma of young people.
A. exposure B. exploration C. expectation D. explosion
在线课程【答案】D
【解析】D考查名词。句意：资源和投资都集中在大城市，导致了人口爆炸和年轻人的困境。A暴露，展览；B探测，探究；C期待，预期；D爆炸，激发。故选D。