People have come to understand _____ prevents so many Americans from  being as happy as one might expect.

A．that it is why

B．what does it that

C．why it does that

D．what it is that

（）　、その　ニュースを　しりました。

A．ちじを　みて

B．きっぷを　かって

C．じしょを　ひいて

D．しんぶんを　よんで