现阶段，对确诊病例和临床诊断病例的密切接触者实施：（）。
A.隔离治疗
B.医学观察
C.居家观察
D.居家隔离
E.无需处理
参考答案：B
---Do you know the famous scientist Yuan Longping?
---Of course. His name______whenever the matter of hybrid rice（杂交水稻）is discussed.
A．comes out
B．comes up
C．comes in
D．comes on
何谓故障安全原则？
