Which sample has the greatest mass?

A.     1 mol of ${\text{S}}{{\text{O}}_{\text{2}}}$

B.     2 mol of ${{\text{N}}_{\text{2}}}{\text{O}}$

C.     2 mol of Ar

D.     4 mol of ${\text{N}}{{\text{H}}_{\text{3}}}$

B