I chose D but the answer is E. I still don't understand why D is wrong.
If the bear population in areas of the Abbimac Valley outside the Kiffer Forest Preserve has decreased, I think it can weaken the conclusion.
So Why can't D be an answer? ...
I picked E but the answer is C. And I still don't understand why E is wrong.
I think E also can weaken the conclusion since it says "The physical effort~~~~does not stimulate circulation enough to warm your hands."
So Why can't E be an answer ...