Why did the institution of slavery develop in africa?

a. africa had too many people.
b. slaves were valued as goods to be sold and traded.
c. european traders introduced slavery to west africa.
d. africa had an excess of land and a shortage of labor.

i'm not sure if it's b or c. !

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".

the industrial revolution pushed the world into modern industrialization. it changed the course of history profoundly. it caused rapid urbanization and pushed cities and countries into development. the industrial revolution began in great britain with a series with new inventions which led to the creation of machines and mass production.

this caused the country to gain wealth and money and become an international superpower. it improved transportation and manufacturing inside the country, pushed people to live in urban areas and britain to become the most powerful nation in the world for a while.