Answer: Option (A) is the correct answer.
Explanation:
Atomic number of sodium is 11 and its electronic configuration is [tex]1s^{2}2s^{2}2p^{6}3s^{1}[/tex].
In order to gain stability, sodium loses one electron and hence it forms a positive ion [tex](Na^{+})[/tex].
Thus, we can conclude that when sodium combines with chlorine, it has a net charge of +1 because sodium loses a negative electron when forming chemical bonds.