单项选择题

A Telephone Message To Mr, Grant Derek Mian, manager of (16) , rang you to see if you had received their (17) for the ’99 National Computer Show. If you have received it and would like to (18) , please (19) as early as possible. Their telephone number is (20) . Da Qing

A.go and see the exhibition
B.let them know
C.write them a letter
D.buy their computer