At the meeting, they sat very ________ and had a _________ talk, but I didn’t know what they were

talking about.[ ]

A. close; close

B. closely; close

C. close; closely

D. closely; closely

数字地球是指建设若干个图书馆，搜集全球各地的数字信息，在网络平台上实现资源共享。