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【单选题】Some pessimistic experts feel that the automobile is bound to fall into disuse. They see a day in the not-too-distant future when all autos will be abandoned and allowed to rust. Other authorities, ho...
A.
How to render automobiles pollution-free.
B.
How to make smaller and safer automobiles.
C.
How to solve the problem of traffic jams.
D.
How to develop an automated subway system.
【多选题】造成物种问生殖隔离的原因是多种多样的，其中合子前隔离是指妨碍种问交配或者在不同物种间试图交配时阻止卵子受精的隔离，它可能是通过以下哪几种隔离方式来实现？（）
A.
时间隔离
B.
生态隔离
C.
行为隔离
D.
机械隔离
E.
杂种不育