Suppose the Interaction Between Two Atoms Has the Effective Potential $t=0$

Multiple Choice

Suppose the interaction between two atoms has the effective potential energy curve shown below:

I have marked the vertical scale on this graph using an arbitrary energy unit we'll call bondits.
-Suppose instead we know that at $t=0$ the atoms are at rest at a separation of $0.4 \mathrm{~nm}$ . What minimum energy is required to break the bond in this case?

A) Only a smidgen (less than a bondit)
B) 5 bondits
C) 10 bondits
D) 15 bondits
E) 20 bondits
F) The bond is already broken (or we can't form a bond) .