Which of these was a reason the american colonies were fighting a war for independence in 1776?

Multiple reasons. Firstly, Britain (a world-wide power) was setting humongous taxes on imported and exported goods. (As in the 'Tea Party' the Americans rebelled by throwing the tea into the sea). The colonies were irritated by this whole control, and wanted more power and say in what taxes were put on them. 

"teotihuacan was the cultural center of the zapotecs".