耐细菌的防水卷材是（）。 A．氯化聚乙烯一橡胶卷材B．氯化聚乙烯卷材C．聚氯乙烯卷材D．三元

What is not stated but implied in the third paragraph？

A．People criticized the royal family severely on Diana's death.

B．People wanted the royal family to learn a lesson from Diana's death.

C．People wanted the royal family to be informal on royal occasions.

D．People needn't bow to royal members, unless they want to.

Lesson Three is (the most) difficult lesson, (but) it isn't (the) most difficult lesson (in) Book Four.

A．the most

B．but

C．the

D．in

A．People criticized the royal family severely on Diana's death.

B．People wanted the royal family to learn a lesson from Diana's death.

C．People wanted the royal family to be informal on royal occasions.

D．People needn't bow to royal members, unless they want to.

In choosing a firewall product, what is implied as the main concern of the author？

A．Management.

B．Transparency.

C．Independence.

D．Efficiency.