Answer: The correct answer is salt.
A compound is a chemical substance which is formed by the combination of two or more elements, joined together in a fixed proportion.
Salt is a chemical compound which is formed by the reaction of an acid with a base. For example- NaCl ( sodium chloride) is a common salt. It is formed by the combination of two elements. Therefore, salt is a compound.
On the contrary, Phosphorous (P), sulfur (S) and Oxygen (O₂) are composed of a single element. Therefore, they are not compounds.
Thus, the correct answer for the compound is Salt .
