The correct option is D It is used as a catalyst along with Cr2O3 in the manufacturing of methyl alcohol from water gas
a) ZnO is amphoteric in nature.
b) It is white when cold and yellow when hot.
c) Cobalt zincate [Co(ZnO2)] is formed:
2ZnO+2Co(NO3)2⟶2Co(ZnO2)+4NO2+O2
d) ZnO is used as a catalyst along with Cr2O3 in the manufracture of methyl alcohol from a mixture of carbon monoxide and hydrogen.