I Would Say The Answer Is C.
Answer and Explanation:
The Fremy salt is a chemical compound its chemical name is disodium nitrosodisuphonate
The molecular formula of the Fremy salt is 
When phenol is treated with Fremy salt in presence of water then benzoquinone is formed
( in presence of Fremy salt and water)
Answer:
1s2 2s2 2p2
Explanation:
it has 6 electrons in two energy levels so the sub levels are 1s, 2s and 2p