Which one among the following is the correct order of amount of lime $(\mathrm{CaO})$, silica $\left(\mathrm{SiO}_2\right)$, alumina $\left(\mathrm{Al}_2 \mathrm{O}_3\right)$ and ferric oxide $\left(\mathrm{Fe}_2 \mathrm{O}_3\right)$ in Portland cement?

• Correct answer
  A

  $\mathrm{CaO} \gt \mathrm{SiO}_2 \gt \mathrm{Al}_2 \mathrm{O}_3 \gt \mathrm{Fe}_2 \mathrm{O}_3$
• B

  $\mathrm{SiO}_2 \gt \mathrm{CaO} \gt \mathrm{Fe}_2 \mathrm{O}_3 \gt \mathrm{Al}_2 \mathrm{O}_3$
• C

  $\mathrm{Al}_2 \mathrm{O}_3 \gt \mathrm{SiO}_2 \gt \mathrm{CaO} \gt \mathrm{Fe}_2 \mathrm{O}_3$
• D

  $\mathrm{Fe}_2 \mathrm{O}_3 \gt \mathrm{Al}_2 \mathrm{O}_3 \gt \mathrm{SiO}_2 \gt \mathrm{CaO}$

Hence, the correct answer is option: 'A'.