单项选择题

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

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热门试题

单项选择题

This evolution of human brains was not without its difficulties for mothers, because ______.

A．human brains started to grow larger
B．our ancestors walked upright on two legs
C．it altered our ancestors' skeletons
D．it makes the passage of big-brained infants difficult

单项选择题

Which is NOT true about the Death with Dignity Act

A．It is passed in Portland, Oregon.
B．It is legal for a doctor to prescribe any fatal drugs.
C．It has been hotly debated for most of its existence.
D．It is a legitimate medical purpose.