问题详情

Influenza
Influenza has been with US a long time. According to some Greek writers ______【51】medical history, the outbreak of 412 B. C. was of influenza. The same has been suggested of the sickness______【52】swept through the Greek army attacking Syracuse in 395 B. C. Flu is a disease that moves most quickly among people living in ______【53】conditions, hence, it is likely to attack armies.
______【54】the nineteenth century there were five widespread outbreaks(教材) of influenza. The last of the five______【55】in 1889 and marked the beginning of the story of influenza in our time.______【56】the recent outbreak, it started in Asia.
For more than forty years before that outbreak, influenza had steadily______【57】and was believed to be dying out. A new group of outbreaks was______【58】by the great outbreak of 1889 - 1890 and for the next quarter of a century flu remained a constant threat.
In April 1918 flu broke out among American troops stationed in France. It quickly spread through all the______【59】but caused relatively few deaths. Four months later, however, a second outbreak started which______【60】to be a killer. It killed not only the old and already sick but also healthy young adults. It______【61】through every country in the world, only a few distant islands in the South Atlantic and the Pacific remaining ______【62】. It brought the life of whole countries to stop, food ______【63】stopped and work loss was very great. Before the great outbreak ended, it had killed at______【64】15 million people. There after there have been several great outbreaks throughout the world. It is thus______【65】that influenza is a terrible infection that we have to pay more attention to.
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A．by
B．on
C．to
D．with请帮忙给出正确答案和分析，谢谢！