Find All Points on the Graph of the Function $f ( x ) = \frac { x ^ { 2 } } { x + 2 }$

Find all points on the graph of the function $f ( x ) = \frac { x ^ { 2 } } { x + 2 }$ where the tangent line is horizontal.

A) (0,0) and (-4,-8)
B) There are none.
C) (0,0)
D) (2,1)