【单选题】In an 8 hour day, Andy can produce either 8 loaves or 24 cakes; Rolfe can produce either 24 loaves or 24 cakes. Andy and Rolfe ________.
A.
can gain from exchange if Andy specializes in cake production and Rolfe specializes in bread production
B.
can gain from exchange if Andy specializes in bread production and Rolfe specializes in cake production.
C.
cannot gain from exchange.
D.
can exchange but only Rolfe will gain.