在延髓中传导运动的纤维束有()A．锥体系 B．内侧丘系 C．脊髓丘脑束 D．外侧丘系

对于数据：80，88，85，83，84．①这组数据的平均数是84；②这组数据的众数是85；③这组数据的中位数是84；④这组数据方差是36．下列说法中正确的有（　　）

A．1个

B．2个

C．3个

D．4个

在矿山开采行业，采用工程技术措施是防止尘肺发生的有效手段。下列选项中，投资较低且效果可靠的技术措施是( )。

A．生产过程密闭化

B．生产过程自动化

C．湿式作业

D．个体防护

Passage Four

According to the passage, which of the following statements is NOT true

A．The potential health hazards of mobile phones call for further research.

B．The Australian scientists find no connection between growth of tumors in human body and radiation from mobile phones.

C．The Italian scientists’ belief is shared by other scientists.

D．The British government inquiry didn’t establish any link between health risks and use of mobile phones.

I am told that her father is in London and ______ a dry-goods store.

A．has kept

B．kept

C．keeps

D．had kept

以下哪个功能不是数据链路层需要实现的______

A．差错控制

B．流量控制

C．路由选择

D．组帧和拆帧