单项选择题
A.They can’t fit into the machine. B.They have not been delivered yet. C.They were sent to the wrong address. D.They were found to be of the wrong type.
A.It has a very long history. B.It is a private institution. C.It was founded by Thomas Jefferson. D.It stresses the comprehensive study of nature.
A.To investigate the causes of AIDS. B.To raise money for AIDS patients. C.To rally support for AIDS victims’ in Africa. D.To draw attention to the spread of AIDS in Asia.