单项选择题
Passage One Questions 17 to 19 are based on the conversation you have just heard.
A．Opposite to the library. B．On the same floor as the labs. C．On the first floor. D．On the ground floor.
A.assume B.confidential C.disagree D.formula E.forthcoming F.illustrating G.mysteriously H.observe I.optimistic J.package K.radically L.reality M.separately N.spoiling O.understimate
A．Fancy product. B．Local handicrafts. C．Traditional Thai silks. D．Unique tourist attractions.