问题
单项选择题
During many sectors are foundering, the $21 billion videogame software industry is booming, adding game developers at a rate of 2,500 a year in the United States alone.
A．When
B．Where
C．Would
D．While
答案
参考答案：D
解析：[分析]词语应用 表示“当……的时候”，“和……同时”常用连词while表并列；因此D为答案。