Blood haemoglobin contains the metal

Coordination compounds are of great importance in biological processes. In this context,which of the following statements is $NOT$ correct?

Assign $A, B, C, D$ from the given type of reaction.
$NiCl_2 + 2dmg \xrightarrow{NH_4OH} Ni(dmg)_2 \downarrow$

Write the application of coordination compounds in black and white photography.

Aqueous solution of a metallic nitrate $X$ reacts with $NH_4OH$ to form $Y$,which dissolves in excess $NH_4OH$. The resulting complex is reduced by acetaldehyde to deposit the metal. $X$ and $Y$,respectively,are

Which of the following is considered as an anticancer species?