Triangles DEF and D'E'F' are shown on the coordinate plane below:

Triangle DEF and triangle D prime E prime F prime with ordered pairs at D negative 1, 6, at E 1, 3, at F 6, 3, at D prime 6, 1, at E prime 3, negative 1, at F prime 3, negative 6.

What rotation was applied to triangle DEF to create triangle D'E'F'?

None of the above

90° counterclockwise

180°

90° clockwise