Both a and c are correct, however I think that A would be the most correct answer in this case.
The constitutional convention was held in Philadelphia, Pennsylvania. The constitution is the Law of the land.
They are elements of rule of law
Yes because a tyrant can and will do whatever he/she wants. I'd rather die than be under the control of a tyrant. In a democracy, I feel like my voice is heard (however small).
Hope this helps!