肝肿大的原因包括()
①黄疸
②充血性心衰
③癌症
A.①
B.①②
C.①②③
D.②③
E.①③
参考答案:D
There is much truth in the idea ________ kindness is usually served by frankness. [ ]
A. why
B. which
C. that
D. whether
流行病学研究对象是()
A.患者
B.非患者
C.人群
D.个体
E.病原携带者