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 whitefooted 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 it would be most useful 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 population is currently limited by the availability of animals for ticks ‘s larval stage to feed on

C. Whether the infected deer 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 transmits to humans.


Was confused between [spoiler]B & D[/spoiler]. Finally chose D. However OA is B.

Can anybody give a clear picture why B?