Your answer choices are cut off. It appears that choice B isn't shown. However, if
-7x = -56
then
x = 8
the result is positive due to the fact that dividing two negatives (-56 over -7) leads to a positive result. As a check, replace x with 8 to get...
-7x = -56
-7*x = -56
-7*8 = -56
-56 = -56
the fact that we get the same value on both sides confirms we have the right answer.