选择题：People are confused in their attempts to control malaria in Europe in the early

题目内容：

People are confused in their attempts to control malaria in Europe in the early 1900s, because scientists ______.

A．identified only one mosquito species instead of six species

B．thought only three mosquito species transmitted disease

C．thought there was only one mosquito species

D．did not know what species was being studied

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Sperm whales can produce stronger ultrasonic waves to kill their prey than dolph

Sperm whales can produce stronger ultrasonic waves to kill their prey than dolphins.A．RightB．WrongC．N

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The fact that comparative advantage of an activity displaces that of the other one could moderate the

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Part Ⅱ Reading Comprehension (Skimming and Scanning)Directions: In this part, you will have 15 minute

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Griffith's film innovations had a direct effect on all of the following EXCEPT ______.A．film editingB

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Television is a ______ in the transmission of message.A．senderB．receiverC．transmitting deviceD．none o

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