On Feb 27, Chinese Premier Wen Jiabao took part in _____ online chat with Chinese netizens, who expressed interests and concerns over property prices, inflation, ________ wealth gap and other social issues
A.the ; aB.an ; /C.the; theD.an ; the在线课程D
解析：
考查冠词。句中an online chat with Chinese netizens一次与中国网民的在线交谈；
the wealth gap and other social issues特指收入差距和其它社会话题，故选D。