we have that
the formula to calculate the slope between two points is equal to
m=(y2-y1)/(x2-x1)
we have
(x1,y1)=A(-3,6)
(x2,y2)=B(3,-6)
substitute the given values in the formula
m=(-6-6)/(3+3)
m=-12/6
m=-2
therefore
option D
-12/6
m=-2
therefore
option