The correct option is A Common salt
Pure water that is completely free of all salts is a bad conductor of electricity. To make it conducting, it should have ions to carry charges. Salts, when dissolved in water, can produce ions that can carry electricity. The chemical formula of common salt is NaCl (Sodium Chloride). It dissociates into sodium ion and chloride ion which act like charge carriers to conduct electricity.
Sugar, glucose, and kerosene do not form ions in water and cannot conduct electricity.