Answer
C. 14
Step-by-step explanation
The area of triangle = 1/2(base)(height)
The height:
the height is the distance from point (2,-3) perpendicular to the base intersecting it at point (2,1)
the height is then the distance between the 2 points = 4
The base:
the base is the distance between points (7,1)and (0,1) = 7
The area:
the area = 1/2 x 4 x 7 = 28/2 = 14 units²