Answer:
KNO₃ is an electrolyte.
Step-by-step explanation:
Electrolyte is any specie which when dissolved in water produces a cation and anoin. Electrolytes has the ability to conduct electricity. In given options O₂, Xe and C₃H₈ are non electrolytes because they cannot dissociate into cation and an anion due to their covalent bonds or monoatomic nature. The dissociation of Potassium Nitrate is as follow,
KNO₃ → K⁺ ₍aq₎ + NO₃⁻ ₍aq₎