On no account ____ ever leave the baby at home alone.

A．Some mothers try to influence their unborn children by studying art and other subjects duringtheir pregnancy.
B．It is utterly impossible for us to learn anything about prenatal development.
C．The blood vessels of mother and child do not join directly.
D．There are no connection between mother’s nervous systems and her unborn child’s.

A．they use proper words to carry their ideas.
B．they both speak truly of their own feelings.
C．they try to understand each other’s ideas beyond words.
D．they are capable of associating meaning with their words.