Lyme disease is caused by a bacterium transmitted to humans by deer ticks. Generally deer ticks pick...

题目信息

Lyme disease is caused by a bacterium transmitted to humans by deer ticks. Generally deer ticks pick up the bacterium while in the larval stage from feeding on infected white-footed mice. However, certain other species on which the larvae feed do not harbor the bacterium. Therefore, if the population of these other species were increased, the number of ticks acquiring the bacterium and hence the number of people contracting Lyme disease-would likely decline.

Which of the following, if true, most strengthens the argument?

A:Ticks do not suffer any adverse consequences from carrying the bacterium that causes Lyme disease in humans.

B:There are no known cases of a human's contracting Lyme disease through contact with white-footed mice.

C:A deer tick feeds only once while in the larval stage.

D:A single host animal can be the source of bacteria for many tick larvae.

E:None of the other species on which deer tick larvae feed harbor other bacteria that ticks transmit to humans.

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正确答案： C:A deer tick feeds only once while in the larval stage.

题目说，鹿虱传染Lyme给你。鹿虱在幼虫时期吃infected 白脚老鼠感染病菌。因为鹿虱幼虫们也吃别的玩意，所以如果增加别的玩意的数量的话, 鹿虱们感染的机会就会比较下。

问什么选项加强。要加强的是增加别的事物的数量。

C说鹿虱们幼虫时期只吃一顿，如果有只有白脚老鼠，那就要感染了。如果有大量其他东西可以吃，鹿虱们吃到白脚老鼠的机会就大大减少。因为他们只吃一次！所以人类感染的可能也小。

B说没有人从和白脚老鼠的直接接触中感染。这个不能加强为什么要增加别的玩意。

题目分析：A围绕的是tick do not suffer这种动物谈的，与原文所谈范围是相反的，杀。B说以前是否有人接触耗子得病的历史，没说过，杀。C说tick这种动物在larval这个阶段只吃一次，原文说过tick在幼虫时进食问题，信息和原文有交叉，留着。D说一个单一的宿主能够是很多细菌的来源，没说过，杀。E说other bacteria，范围显然不对，杀。

笔记