The intermolecular potential energy for the molecules $A-A$,$A-B$,$A-C$ and $A-D$ given below suggests that:

• A
  $D$ is more electronegative than other atoms
• B
  $A-D$ has the shortest bond length
• C
  $A-B$ has the stiffest bond
• D
  $A-A$ has the largest bond enthalpy