单项选择题

关于病原菌的致病因素，错误的是

A.病原菌有黏附因子
B.病原菌有荚膜、微荚膜
C.与病原菌的胞外酶有关
D.与病原菌的内、外毒素有关
E.与病原菌侵入的数量并无密切关系
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社会主义新闻事业怎样做到向党负责和向人民负责的统一?
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TEXT BScience writer Tom Standage draws apt parallels between the telegraph and the gem of late 20th century technology, the Internet. Both systems grew out of the cutting edge science of their timE.The telegraph's land lines, underwater cables, and clicking gadgets reflected the 19th century's research in electromagnetism. The Internet's computers and high-speed connections reflect 20th century computer science, information theory, and materials technology.But, while inventions make a global network possible, it takes human cooperation to make it happen. Standage's insight in this regard adds depth to his technological history. It underscores the relevance to our own time of the struggles of Samuel Morse in America, William Cooke in England, and other telegraph pioneers. They made the technology work efficiently, sold it to a skeptical public, and overcame national and international bureaucratic obstacles. The solutions they found smooth the Internet's way today..Consider a couple of technical parallels. Telegrams were sent from one station to the next, where they were received and retransmitted until they reached their destination. Stations along the way were owned by different entities, including national governments. Internet data is sent from one server computer to another that receives and retransmits it until it reaches its destination. Again the computers have a variety of owners.Then there is the social impact. The Internet is changing the way we do business and communicatE.It makes possible virtual communities for individuals scattered around the planet who share mutual interests. Yet important as this may turn out to be, it is affecting a world that was already well connected by radio, television, and other telecommunications. The Associated Press, Reuters, and other news services would have spread the Star report quickly without the Internet. In this respect, the global telegraph network was truly revolutionary ---- the unprecedented availability of global news in real time gave birth to the Associated Press and Reuters news services. It gave a global perspective to newspapers that had focused on local affairs. A provincialism that geographical isolation had forced on people for millennia was gone forever. Some seers naively hailed this as a force for world peacE.They predicted that tensions over cultural and ethnic differences would relax as people interacted in real timE.Visionaries say the same about the Internet. While communications can smooth this process, they do not automatically make it happen. As the experience of the past century and a half has shown, peace takes the will to make it work and sustained effort by all parties.What does 'the gem of late 20th century technology' refer to?[A] The telegraph.[B] Information theory.[C] Materials technology.[D] The Internet.
A.But,
B..
Consider
C.
Then
D.
What
E.
[C]
F.
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