Tom Takes 20 Minutes to Burn a CD and 5

Tom takes 20 minutes to burn a CD and 5 minutes to make a sandwich. Jerry takes 15 minutes to burn a CD and 3 minutes to make a sandwich. Both individuals will be better off if

A) Jerry trades sandwiches in exchange for CDs.
B) Tom trades sandwiches in exchange for CDs.
C) they trade, no matter who trades sandwiches and who CDs.
D) they don't trade.