The cotton gin was an important invention because a) it inadvertently led to the spread of slavery. b) it made cotton much easier for slaves to pick. c) it prevented insects from damaging the cotton. d) it caused people to stop needing so much cotton.

A) it inadvertently led to the spread of slavery.

Explanation:

The cotton gin was a particularly important invention because it changed the economy and society of the Southern United States. The cotton gin is a machine that can separate cotton fibers from seeds. This leads to higher productivity. As productivity increased, cotton became a more profitable business, and in turn, this led to an enormous growth of slavery in the American South.

im pretty sure it has something to do with the end of ww1

i really really really really really really dont know