This is because sodium loses electrons so it is oxidized to sodium ions in NaCl, and the chlorine gains electrons so it is reduced to chloride ions in NaCl, since both oxidation and reduction happen, it is a redox reaction.
The correct answer is Two different elements take part in the reaction.
Explanation:
A redox reaction is generally defined as chemical reaction in which oxidation and reduction takes place simultaneously.It is a reaction between two species among which gain and loss of electrons takes place.
