Find the coordinates of the midpoint of the segment whose endpoints are given.
p1 p2 m
(3, 5) (-7, -5)

The coordinates of the midpoint of a line segment are the average of the abscissas and ordinates of the end points.
          (abscissa)     (3 + -7) / 2 = -2
          (ordinate)       (5 + -5) / 2 = 0
the coordinate of the midpoint of this line segment is (-2, 0). 

The answer to your question is the last one