In the Hypothetical Atomic Interaction Shown in Figure C9 $0.25 \mathrm{~nm}$

In the hypothetical atomic interaction shown in figure C9.13, assume that the atoms initially have zero radial velocity at a separation of $0.25 \mathrm{~nm}$ . If the atoms are jostled slightly so that the system gains a slight amount of energy, what happens to the atoms' separation afterward?

A) It oscillates within a small region about $r=0.25 \mathrm{~nm}$ .
B) It oscillates between $r=0.25 \mathrm{~nm}$ and $r=0.05 \mathrm{~nm}$ .
C) It directly increases toward infinity.
D) It eventually increases toward infinity, maybe directly but maybe after one detour to smaller separations.
E) So me other behavior (specify) .