A rubber band of negligible thickness encloses three pegs that lie in a perfect line, as shown. Each peg has a diameter of 4 cm, as shown. What is the length of the rubber band used, in centimeters? All pegs shown are congruent circles.
[asy]
size(120);
draw(circle((0,0),1));draw(circle((0,2),1));draw(circle((0,4),1));
dot((0,0)^^(0,2)^^(0,4));
draw((-1,0)--(-1,4)--arc((0,4),1,180,0)--(1,4)--(1,0)--arc((0,0),1,360,180),linewidth(2));
draw((-1,0)--(1,0),dotted);
label("4 cm", (-0.38,0)--(1,0), N);
[/asy]
<spanclass=′latex−bold′>(A)</span>8<spanclass=′latex−bold′>(B)</span>8+4π<spanclass=′latex−bold′>(C)</span>16+4π<spanclass=′latex−bold′>(D)</span>16+8π<spanclass=′latex−bold′>(E)</span>16π