An element has a crystalline structure where the unit cell is a cube with one atom at each corner and two atoms on its body diagonal. If the volume of this unit cell is $24 \times 10^{-24} \, cm^3$ and the density of the element is $7.2 \, g \, cm^{-3}$,then the number of atoms present in $200 \, g$ of the element is:

• A
  $3.472 \times 10^{24} \, \text{atoms}$
• B
  $4.972 \times 10^{24} \, \text{atoms}$
• C
  $5.345 \times 10^{24} \, \text{atoms}$
• D
  $4.478 \times 10^{24} \, \text{atoms}$