Bella its me jordan reply please

Which of the following inventions most directly allowed ancient farmers to produce a surplus ?

Which of the following led to a continuation of the treatment in the excerpt above? a)the brutality of the trans-atlantic african slave trade. b)spanish repression after violent native uprisings in new spain during the 16th century. c)european competition to quickly establish colonial holdings in the new world. d)the reliance of the spanish on native americans to provide labor under the encomienda system.

How long have counties been a part of the government structure of the united states?