单项选择题

A.PaO为50mmHg,PaCO为40mmHg
B.PaO为55mmHg,PaCO为50mmHg
C.PaO为65mmHg,PaCO为40mmHg
D.PaO为70mmHg,PaCO为40mmHg
E.PaO为70mmHg,PaCO为45mmHg