Explanation

(d)
Number of moles of oxygen =$\frac{80}{16}$
Number of atoms of oxygen = $\frac{80}{16} \times N_{0} \times 2$
= $5 \times N_{0} \times 2$
Number of moles in 5 g of hydrogen = $\frac{5}{1}$
Number of atoms in 5 g of hydrogen =$5 \times N_{0} \times 2$
Hence, the number of atoms in 80 g of oxygen is equal to the number of atoms in 5 g of hydrogen.