Europeans usually obtained slaves in Africa by which method?
A) promising them freedom if they worked in America
B) defeating their kingdom in battle
C) killing their leaders
D) buying them

D. Buying them.

Explanation:

The Trans-Atlantic Slave Trade flourished between 1450 and the end of the 19th century. European traders - Portuguese, Spanish, French, English, Dutch - arrived in their ships and bought local men, women and children. They could also organized campaigns to hunt for slaves in the area, or bought people from local merchants and rulers.  The local kings or lords in West Africa were actively involved in selling his own people as slaves for the large profitability of it.

i am not 100% positive but i think it is is b. both are non-partisan jobs

i am pretty sure that members of congress have term limits, can be impeached, and are nominated through direct popular vote.