The reactivity of the metals $\mathrm{Al}, \mathrm{Ca}, \mathrm{Mg}$ and Na follows the order

• Correct answer
  A

  $\mathrm{Na} \gt \mathrm{Ca} \gt \mathrm{Mg} \gt \mathrm{Al}$
• B

  $\mathrm{Na} \gt \mathrm{Mg} \gt \mathrm{Ca} \gt \mathrm{Al}$
• C

  $\mathrm{Al} \gt \mathrm{Mg} \gt \mathrm{Ca} \gt \mathrm{Na}$
• D

  $\mathrm{Mg} \gt \mathrm{Na} \gt \mathrm{Ca} \gt \mathrm{Al}$

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