sulfur (S) argon (Ar) fluorine (F) bromine (Br)
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: An atom of which element contains one more proton than one atom of chlorine (Cl)?
Possibilities:
- sulfur (S)
- argon (Ar)
- fluorine (F)
- bromine (Br)

argon (Ar)