Which of the following statements is not correct ?

Question

$\begin {array} {1 1} (A)\;\text{ZnO is a white powder and its colour changes to yellow on heating and becomes again white on cooling} \\ (B)\;\text{ZnO is an amphoteric oxide} \\ (C)\;\text{ZnO is used as a white pigment in paints} \\ (D)\; \text{Zno is a non-toxic compound and is blackened by atmospheric hydrogen sulphide} \end {array}$