I believe the answer is E
Hope this helps!
B. and E. marked the downfall of the Inca empire, for obvious reasons. Disease and civil war would obviously kill the empire, and taking an important leader would also mark great chaos within the empire. A. and C. are not to be ignored however, considering that maintaining peaceful relationships with the Spaniards only brought death and chaos to the Aztecs, all from the Spaniards.
Spartans feared the Messenians because of thier wealth and for thier influence in other cities.
"<span>Social stratification developed based on newly specialized jobs" is the best option from the list, since this was due to the recent ability to domesticate plants and animals.</span>