Consider the figure consisting of a square, its diagonals, and the segments joining the midpoints of opposite sides. The total number of triangles of any size in the figure is[asy]
size(100); defaultpen(linewidth(0.7)); draw(unitsquare^^(0,0)--(1,1)^^(0,1)--(1,0)^^(.5,0)--(.5,1)^^(0,.5)--(1,.5));[/asy]<spanclass=′latex−bold′>(A)</span>10<spanclass=′latex−bold′>(B)</span>12<spanclass=′latex−bold′>(C)</span>14<spanclass=′latex−bold′>(D)</span>16<spanclass=′latex−bold′>(E)</span>18