I need help with b) c) and what is the electronic configuration of atom E

Answer:
(b) A and C belongs to same group.
(c) D is a non metal.
Explanation:
The Electronic Configuration of E is
[tex]1s {}^{2} 2s {}^{2}2p {}^{6} 3s {}^{2} 3p {}^{6} 4s {}^{2} [/tex]