It's the most traditional and ancient one in the world. These economies still produce products and services that are a direct result of their beliefs, customs, traditions, religions, etc. These areas tend to be rural, second- or third-world, and closely tied to the land, usually through farming. However, there is an increasingly small population of nomadic peoples. They never see profit and surplus.
"After the Industrial Revolution, goods were produced mainly by machines <em>instead</em> of by hand" is the only logical and grammatically correct answer.
