The correct answer - option C.Analysis1. Humans get Lyme Disease (LD) from infected ticks
2. Ticks get infected by feeding on animals with LD
3. Rate of transfer of LD to ticks is low for most animals
4. Exception to the above is - white footed mice (readily pass LD to ticks)
5. Where Biodiversity is in decline, white footed mouse populations expand.
Question: The information give supports which of the following. This is an inference question. Not a strengthen question - A strengthen question would be more on the lines of "which of the following statements support <some claim made in the argument>?".
Here, we need to find what can logically be inferred based on the given information (i.e. supported by the given information).
Combining Statements 1,2,4 and 5, we can infer that -
in areas of low biodiversity,
-> White mouse population will be less (as compared to places of high biodiversity)
-> As a result, number of infected ticks is likely to be higher
-> Number of humans getting LP from infected ticks is likely to be higher
Let us look at the options.
(A) In areas where many humans are infected with Lyme disease, the proportion of ticks infected with Lyme disease is especially high.
Not necessarily true. It may be so that the proportion of ticks with LD is not particularly high, but the Number of humans infected/tick is actually high (i.e. small proportion of infectious ticks passing LD to multiple humans, rather than a large number of infectious ticks).
(B) Very few animals that live in areas where there are no white-footed mice are infected with Lyme disease.
Out of scope. we cannot infer that very few other animals are infected with LD in areas where no WF mice exist. We only know that transmission to ticks, from other host animals is rare - this does not imply that other animals do not exist which do not have LD
(C) Humans are less at risk of contracting Lyme disease in areas where biodiversity is high.
Correct. If Biodiversity is high, the WF mouse population will be less, which means lesser likelihood of infected ticks, and therefore lesser likelihood/risk of humans getting LD. This is as per our pre-thinking.
(D) Ticks feed on white-looted mice only when other host species are not available to them.
No information in the passage to make such an inference. Ticks may feed on WF mice even if other species are available.
(E) The greater the biodiversity of an area, the more likely any given host animal in that area is to pass Lyme disease to ticks.
We only know that greater the biodiversity, lesser is the population of WF mice. Which means the probability of ticks getting infected with LD will reduce (as the WF mice numbers reduce). This option goes in the opposite direction.
Hope this helps.
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