Triangle ABC is rotated to form △A'B'C' .
The coordinates of point A are (1, 1) , the coordinates of point B are (3, 1) , and the coordinates of point C are (1, 4) .
Which rotation around the origin results in the transformation of △ABC to △A'B'C' ?
A. rotation of 90 degrees
B. rotation of 180 degrees
C. rotation of 360 degrees