The volume occupied by a single $CsCl$ ion pair in a crystal is $7.014 \times 10^{-23} \ cm^{3}$. The smallest $Cs^{+}-Cs^{+}$ inter-nuclear distance is equal to the length of the side of the cube corresponding to the volume of one $CsCl$ ion pair. The smallest $Cs^{+}-Cs^{+}$ inter-nuclear distance is nearly:

• A
  $4.3 \ \mathring{A}$
• B
  $4.5 \ \mathring{A}$
• C
  $4.4 \ \mathring{A}$
• D
  None of the above