The characteristics properties of a base in aqueous solution is due to the presence of

Explanation

The correct answer is Hydroxide ions. In an aqueous solution, bases dissociate to produce hydroxide ions (OH-), which are responsible for the characteristic properties of basic solutions, such as a slippery feel and a high pH. Option A, hydride ions, are not commonly present in aqueous solutions and are not responsible for basicity. Option B, hydronium ions, are associated with acids, not bases. Option D, oxide ions, are incorrect because in aqueous solution, oxides would typically react with water to form hydroxide ions, not remain as oxide ions themselves.