$A$ compound $A$ is used in paints instead of salts of lead. Compound $A$ is obtained when a white compound $B$ is strongly heated. The compound $B$ is insoluble in water but dissolves in $NaOH$ solution,forming a solution of compound $C$. The compound $A$ on heating with coke gives a volatile metal $D$ and a gas $E$ which burns with a blue flame. Identify the possible species $D$ and $C$ respectively.

• A
  $D - Hg, C - Hg(OH)_2$
• B
  $D - Cd, C - Na_2[CdO_2]$
• C
  $D - Zn, C - Na_2ZnO_2$
• D
  $D - Zn, C - Zn(OH)_2$