The textbook uses examples of mutilated, artificially sweetened lemons and toasters turned into coffeepots to illustrate the idea that

a$.$

in some categories $($but not others$),$ members retain their category membership even if their appearance changes dramatically.

b$.$

typicality is necessary but not sufficient for category membership.

c$.$

category membership has nothing to do with judgments of typicality.

d$.$

both artifacts and natural kinds can change their category membership by changing surface characteristics