People who have spent a lot of time in contact with animals often develop animal-induced allergies, a significant percentage of which are quite serious. In a survey of current employees in major zoos, about 30 percent had animal-induced allergies. However, a zoo employee who develops a serious animal-induced allergy is very likely to switch to some other occupation.

Which of the following hypotheses receives the strongest support from the information given?

【选项】Exposure to domestic pets is, on the whole, less likely to cause animal-induced allergy than is exposure to the kinds of animals that are kept in zoos.