A-A+
Human babies are born in immature helpless st
问题详情
Human babies are born in immature, helpless states, owing to ______.
A．the early birth of human fetuses
B．the big brains of the fetus
C．the constricted birth canals of the mother
D．both big brains and constricted birth canals
参考答案
正确答案：A
解析：参见文章第4段：And so natural selection encouraged the early birth of human fetuses, before they had finished gestating. For that reason, our babies are born in immature, helpless states compared with those of the apes．其大意是，因此自然淘汰鼓励了人类胎儿的早出生，在他们尚未孕育完之前就出生。正是由于此原
