SSC GD 2023 PYQ — Question 27

The correct answer is option 4 i.e. Mg.

Magnesium is the element with atomic number 12.

• This is the electronic setup for Mg = 1s², 2s²2p⁶, 3s².
• The outermost shell has two electrons, making it a member of the IIA group.
• The outermost shell of magnesium is n = 3, denoting the third period.