How many moles of electron weight one kilogram ?

Question

$(a)\;6.023 \times 10^{23} \\ (b)\;\large\frac{1}{9.108} \times \normalsize 10^{31}\\(c)\; \frac{6.023}{9.108} \times 10^{54} \\(d)\;\large\frac{1}{9.108 \times 6.023} \times \normalsize 10^8$