On a coordinate graph, the points A(-5, 6), B(2, 6), C(2,-1) and D(-5,-1) are the vertices of a square. What is the area of the square?
O A. 7 square units
O B. 14 square units
O C. 28 square units
O D. 49 square units
O A. 7 square units
O B. 14 square units
O C. 28 square units
O D. 49 square units