Final answer:
Buttercup is a foil for the most beautiful women in the beginning of the chapter because she is a tomboy.
Step-by-step explanation:
Buttercup is a foil for the most beautiful women in the beginning of the chapter because she is a tomboy and does not fit the traditional image of beauty. While the most beautiful women focus on their appearance and try to be princesses, Buttercup is more interested in adventure and does not conform to societal expectations of femininity.