When humans first started to appear they had yet to figure out how to farm or fish. However they knew how to hunt animals using spears and such. They also were gatherers because they gathered berries. Later in the human race farming and fishing came into play. So I say A. Hunters......Gatherers.
Okay, well a plow is used for farming. Basically the Sumerian plow is like a modern day tractor. If you have ever heard the term, "to plow the fields", you would know and immediately think of a tractor.
