The main purpose of most constitutions out of these possibilities is D) to define and limit government power. It is usually not E) to give the government absolute power, but is a possibility. It is also not necessarily A) to define a moral code for the people to follow, and it also is not necessarily C) to prevent a strong central government because often constitutions create strong central governments.
For the first question, the answer is true and for the second one, the answer is C. America was the first to send a man to the moon