The metal oxide which can react with acid as well as alkali is
Aluminium oxide
The explanation for the correct answer
The metal oxide which can react with acid, as well as alkali, is Aluminium oxide. Aluminum oxide is amphoteric in nature.
When reacted with HCl, it acts as a base to form the salt AlCl3. When reacted with NaOH, it acts as an acid to form NaAlO2.
Hence, option C is correct.