The right answer for the question that is being asked and shown above is that: "D. indirect democracy." The form of government is the us federal government is that of indirect democracy. That is, federal government is not that showing what a democratic country is.<span>
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I'm sure the answers d, because it would help way more than the other options you'd want to know first hand what happen the only way to do so is to speak to those who fought in the war.
Maurya Empire and Gupta Empire are the most significant but there has been more than that.
Hope this helps!
I think the answer is the 10th Amendment