Answer:
D is the answer.
Step-by-step explanation:
It's all of the above. Facts are just statements about what is currently known. Things can change and quite frequently do. Newtons mechanics is far different than that of Einstein, yet both were declared true in their time.
So A is true
B is also true. The guesses of great minds often get tested and turn out to be right.
C That's the definition of a fact, but the truth is that a fact can be found to be incomplete.