Sam and Christine both run their own lawn care businesses. Sam can mow a lawn in 30 minutes and trim a lawn in 20 minutes: Christine can mow a lawn in 20 minutes and trim a lawn in 20 minutes
Who has absolute and comparative advantage in trimming lawns?
А
Sam has comparative advantage in trimming lawns; no one has absolute advantage in trimming lawns. 
B
Christine has comparative advantage in trimming lawns; no one has absolute advantage in trimming lawns. 
С
Christine has absolute and comparative advantage in trimming lawns. 
D
Sam has absolute and comparative advantage in trimming lawns.