In the figure, squares OABC and ADEF are shown in the rectangular coordinate plane, each with one side on the x-axis. The vertex F is the midpoint of the side on which it lies in square OABC, which has a side length of 4 units.
Accordingly, which of the following is the vector $\overrightarrow { O B } + \overrightarrow { O E }$?
A) $( 4,6 )$
B) $( 8,6 )$
C) $( 10,4 )$
D) $( 10,6 )$
E) $( 10,8 )$