Right choice is (a) Glucose oxidase
To explain I would say: As glucose oxidases transfers electrons from glucose to oxygen atoms (redox reaction), it is an example of oxidoreductases. Glutathione synthetase is an example of ligases as this enzyme is involved in synthesis of new products. Aspartate aminotransferase transfers amino group from aspartate forming glutamate, and hence it is an example of transferase class of enzymes. Histidase is involved in removal of amino group from histidine. Thus, histidase is an example of lyases.