Assuming you are referring to the map I've attached below, the correct answer should be
Huayuna Capac.
It says on the map that it is the Incan Empire. The only ruler of the Incan Empire among these people was Huayna Capac. Moctezuma I was an Aztec emperor, whereas Pacal the Great and Ac Kan were Mayan rulers.
Answer: With the invention of the cotton gin, it meant that more cotton could be processed by less workers ( most of the workers were slaves) in less time so the need for more slaves in that area became unnecessary. The cotton gin could process 50 pounds of cotton a day with a small crew of 2 or 3.
Explanation: