下列关于保护价格的说法中，正确的有（）。A.总是高于均衡价格 B.总是低于均衡价格

人类工效学是理解和把握人体的自然尺度的基础上，充分了解人类的工作能力及其限度，使之合乎人体解剖学、生理学、（）特征的一门科学。

逆行胰胆管造影最常见的并发症是（）。

A.胰腺炎

B.胆管炎

C.胆管穿孔

D.腹膜炎

E.出血

公安机关在加强警民联系方面开拓的新渠道不包括( )。

A．开通了110报警服务台

B．利用电台、电视台等新闻媒体开设了警务专题节目和热线电话

C．建立了巡警，密切了警民的联系

D．进入社区暗访

When I was looking for a Christmas present for my daughter in a toy store, a nicely dressed little girl, with some money in her little hand, was looking at some beautiful dolls. When she saw a doll she liked, she would ask her father if she had enough money. He usually said yes.
At the same time, a boy, with old and small clothes, was looking at some video games. He, too, had money in his hand, but it looked no more than five dollars. Each time he picked up one of the video games and looked at his father, he shook his head.
The little girl had chosen her doll, a very beautiful one. However, she noticed the boy and his father. She saw the boy give up a video game with disappointment and walk to another corner of the store.
The little girl put her doll back to the shelf and ran over to the video game. After she talked to her father, she paid for the video game and whispered(耳语) to the shop assistant.
So the boy got the video game that he wanted for free—he was told it was a prize from the store. He smiled happily, although he felt it was so incredible. The girl saw all this happen. She smiled, too.
When I walked out of the store to my car, I heard the father ask his daughter why she had done that. I would never forget their short talk. " Daddy, didn’t Grandma want me to buy something that would make me happy"
He said, "Of course, she did. "
"Well, I just did!" With that, the little girl started skipping towards their car happily.

The underlined word "incredible" most probably means "______" in Chinese.

A．难以置信的
B．令人兴奋的
C．感到绝望的
D．荒谬可笑的

煤是一种性质十分复杂的由（）和（）组成的混合物。