(Figure: Biscuit and Cookies PPFs) Greg and Melissa Face the Production

(Figure: Biscuit and Cookies PPFs) Greg and Melissa face the production possibilities frontiers shown for biscuits and cookies. Assume that Greg and Melissa trade 60 biscuits for 60 cookies after they have completely specialized in producing the good in which they have a comparative advantage. We know that Greg and Melissa are each made better off with specialization and trade than acting alone because:

A) they are both producing outside of their production possibilities frontier.
B) they are both consuming outside of their production possibilities frontier.
C) Greg is producing outside of his production possibilities frontier.
D) Melissa is producing outside of her production possibilities frontier.