水情预报要求（）总结一次。A、每月度 B、每季度 C、每年度 D、每周

The population of elephant seals, reduced by hunting to perhaps a few dozen animals early in this century, has soared under federal protection during the last few decades. However, because the species repopulated itself through extensive inbreeding, it now exhibits a genetic uniformity that is almost unparalleled in other species of mammals, and thus it is in far greater danger of becoming extinct than are most other species.
Given the information in the passage above, which of the following is most likely the reason that other species of mammals are leas likely than elephant seals to become extinct ？（）

A．Other species of mammals have large populations, so the loss of a few members of the species is not significant.

B．Other species of mammals have increased their knowledge of dangers through the experience of generation after generation of animals.

C．In other species of mammals, hunters can readily distinguish between males and females or between young animals and adults.

D．In other species of mammals, some members of the species am genetically better equipped to withstand a disease or event that destroys other members of the species.

E．Other species of mammals have retained habits of caution and alertness because they have not been protected as endangered species.

对于成套设备、大型机械产品和交通工具的交易，一般采用的清偿贷款方式是( )。

A．分期付款和托收

B．延期付款和信用证

C．信用证和托收

D．分期付款和延期付款

妊娠合并风湿性心脏病，早期心力衰竭的最可靠诊断依据

A．心界扩大
B．心尖部闻及Ⅱ级收缩期杂音
C．肺底部持续性湿啰音
D．休息时心率大于每分钟110次
E．踝部凹陷性水肿

高脚屋的主要缺点是（）。

A、不抗震

B、不抗风

C、不接地气

D、容易倒塌

清洁卫生的程序为（）。

A.先清洁区，再污染区，最后半污染区

B.先污染区，再半污染区，最后清洁区

C.先半污染区，再污染区，最后清洁区

D.先清洁区，在半污染区，最后污染区