Question ID:PT32 S1 Q12 Passage:Navigation in animals is defined as the animal's ability to find its way from unfamiliar territory to points familiar to the animal but beyond the immediate range of the animal's senses.  Some naturalists claim that polar bears can navigate over considerable distances.  As evidence, they cite an instance of a polar bear that returned to its home territory after being released over 500 kilometers (300 miles) away. Stem:Which one of the following, if true, casts the most doubt on the validity of the evidence offered in support of the naturalists' claim? Correct Answer Choice:BChoice A:The polar bear stopped and changed course several times as it moved toward its home territory. Choice B:The site at which the polar bear was released was on the bear's annual migration route. Choice C:The route along which the polar bear traveled consisted primarily of snow and drifting ice. Choice D:Polar bears are only one of many species of mammal whose members have been known to find their way home from considerable distances. Choice E:Polar bears often rely on their extreme sensitivity to smell in order to scent out familiar territory.