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 by feeding on infected white-footed mice. However, certain other species on which the larvae feed do not harbor the bacterium. If the population of these other species were increased, more of the larvae would be feeding on uninfected hosts, so the number of ticks acquiring the bacterium would likely decline.
Which of the following would it be most important to ascertain in evaluating the argument?
A. Whether populations of the other species on which deer tick larvae feed are found only in areas also inhabited by white-footed mice
B. Whether the size of the deer tick population is currently limited by the availability of animals for the tick's larval stage to feed on
C. Whether the infected deer tick population could be controlled by increasing the number of animals that prey on white-footed mice
D. Whether deer ticks that were not infected as larvae can become infected as adults by feeding on deer on which infected deer ticks have fed
E. Whether the other species on which deer tick larvae feed harbor any other bacteria that ticks transmit to humans
我觉得LZ翻译没问题, 但B对是因为: 题中问的是to evaluate the argument..也就是它的有效性. if deer ticks are not limited by the availability of those animals, then its ineffective to increase the the population of other species, since they can still choose to feed on the infected white-footed mice. on the other hand, if the size of the deer ticks population is limited by that, then the increase in the population of other animals will result in that deer ticks have to feed on the increase part of other species,leading to the decrease in the number of ticks acquiring the bacterium..作者: williams 时间: 2010-10-4 06:47
