Help with history multiple choice?

Which of the following most accurately describes the political structure of the Maya from 600 ce to 900 ce?

a. numerous, independent, warring city-states

b. A highly centralized, aggressively expansionist empire

c. several weak vassal kingdoms under aztec domination

d. numerous small coastal villages dependent upon maritime trade

e. sparsely populated religious administrative centers

and please explain why you picked the one you did....i have to give a presentation about this question.....and i think i know the answer but i have to disprove the other choices, and i dont know how