I'm a bit rusty on these, but the density should be the mass of the 4 atoms of rhodium that make up the face centred cubic cell, divided by the volume of the cell.
The correct answer should be (c).
First, convert pm into cm:
Next, work out the volume of the FCC cell:
Next work out the average mass of 1 atom of rhodium: 102.9 g/mol divided by
Next, work out the mass of the 4 rhodium atoms in the FCC unit cell:
Finally, work out the density by dividing this last value by the volume of the FCC cell:
Rounding up, closest answer is (c).