--Excuse me. Can you tell me      I can get to the post office?

-- Take the subway.

A．how

B．what

C．when

D．Where

苯巴比妥的乙醇溶液澄清度检查物质是（）

A．苯丙二酰脲

B．酸性杂质

C．2-苯基丁酰胺

D．对氨基酚

E．苯基丁酰脲