Which of the Following Is a Good Example of Efficient

Multiple Choice

Which of the following is a good example of efficient specialization and voluntary exchange?

A) A college professor hires someone to rototill his or her garden to ready it for spring planting.
B) A college professor works on the engine of a car for a neighbor who is a mechanic.
C) A lawyer decides to babysit his or her young child and agrees to do so for others for cash.
D) A physician agrees to help a neighbor work on his or her income tax return in exchange for his or her bookkeeping services.