We are given the coordinates of one end of a segment PC (P = (11, 12), and also the location of its midpoint O = (4.6)
So we apply the formula that gives us how to reach the midpoint from one of the endpoints of the segment.
From the point P (11, 12) we get to (4, 6) by doing the following:
the y coordinate is lowered in 6 units (from 12 to 6), and the x coordinate iis moved to the left by 7 units (from 11 to 4).
So we can do the same starting from the midpoint to reach the other end of the segment:
From coordinate y = 6 go down 6 units getting to y = 0
and from x-coordinate x = 4 go 7 units to the left getting to x-coordinate -3.
Therefore the other end of the segment (point C) is located at (-3, 0).
Which agrees with the second answer given to you in the list of possible choices.