按照美国FDA药物毒性妊娠分级标准，左旋甲状腺素钠属于（）
A.A级
B.B级
C.C级
D.D级
E.X级
参考答案：A
The winner of the Nobel Prize in Literature 2012, Mo Yan , said he did not have high for winning． Actually, he thought he only had a slim chance to win．
A．assumption
B．expectation
C．satisfaction
D．impression
下列蕨类植物可供我们食用的是〔〕
A．卷柏
B．满江红
C．铁线蕨
D．蕨
