Both Dave and Caroline produce sweaters and socks. If Dave's opportunity cost of producing 1 sweater is 3 socks, and Caroline's opportunity cost of producing 1 sweater is 5 socks, then
a. Dave has a COMPARATIVE ADVANTAGE in the production of sweaters.
b. Caroline has a COMPARATIVE ADVANTAGE in the production of sweaters.
c. Dave has a COMPARATIVE ADVANTAGE in the production of socks.
d. Dave has a COMPARATIVE ADVANTAGE in the production of both sweaters and socks.