Answer : Option D)
.
Explanation : The acid base theory of Bronsted-Lowry, stated the definition of acids and bases on the basis of conjugated.
The fundamental concept of this theory states that when an acid and a base reacts with each other, the acid forms its conjugate base, and the base forms its conjugate acid by exchanging the proton.
So, in the given reaction;

It is firstly observed that the species
is accepting a proton from the acid, therefore this is one of the bases.
Secondly,
accepts the proton and forms the reactant again in the reversible reaction.
Therefore, these are the correct options.
