Answer:
Statistics are always on a high alert for our lifes destination
It would be a. "We the people of the United States ... do ordain and establish this Constitution for the United States of America."
We can rule out c immediately, because it has dependent clauses standing on its own. B. can also be ruled out, because the clause in-between the hyphen does not read correctly. A. is correct grammatically, but D. is also grammatically correct and it explains it in a quick and understandable way.
C!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
in that paragraph, the expression Mounting evidence could be a bit confusing, but it indicates that there's been reaserch about it before, and that it all points in the same direction, the more research proving the same point means the data is convincing. The answer is D.