检索外文期刊全文，下列数据库，首选哪个？（）
A.ElsevierSDOS
B.CA
C.wiley化工类工具书
D.PQDT
参考答案：A
—Would you mind my using your dictionary?
—________.
A．Yes, please
B．Of course not
C．You are welcome
D．My pleasure
