One study found that if participants were told a new fact about robins, they would also believe that the new fact was true of ducks. However, if told a new fact about ducks, participants would not extrapolate this information to robins. This suggests that

a$.$

participants are willing to apply inferences from a typical case within a category to the whole category but will not apply inferences from an atypical case to the whole category.

b$.$

participants treat each category member independently $($on a case$-$by$-$case basis$)$ when applying new beliefs.

c$.$

beliefs within a theory are less likely to affect typical category members than atypical ones.

d$.$

new knowledge about a member of a category is unstable, leading to a change in a person$$s belief system only on rare occasions.