Which of the following aqueous solution will conduct an electric current quite well in comparision?

The correct option is B

HCl

Substances that give ions when dissolved in water are called electrolytes. They can be divided into acids, bases, and salts because they all give ions when dissolved in water. These solutions conduct electricity due to the mobility of the positive and negative ions, which are called cations and anions respectively. Hence an aqueous solution of an electrolyte will conduct an electric current easily. HCl is an electrolyte, as it dissociates into hydrogen ion (cation) and chloride ion (anion). In other cases, there is no ion formation and hence they are not used as electrolytes.