关于动脉导管未闭的描述，错误的是

A．由左侧第一对主动脉弓演变而来

B．出生1年后动脉导管仍然开放

C．分圆柱形、漏斗形和缺损形3型

D．胸骨左缘第2肋间可闻及机器样杂音，伴震颤

E．有周围血管搏动征

Once you have established the daily ration of drinking water in a survival situation，how should you drink it?（）

A.Small sips at regular intervals during the day

B.The complete daily ration at one time during the day

C.One-third the daily ration three times daily

D.Small sips only after sunset