On the real number line below, with coordinates as labeled, an object moves according to the following set of instructions: from point $P$ the object moves right to $Q,$ then left to $R,$ then right to S$,$ and finally left until it returns to its original position at $P.$ What is the closest estimate of the total length, in coordinate units, of the movements this object makes?

A$.0$

B$.4$

C$.12$

D$.22$

E$.36$