Identify the use of $EDTA$ from the following.

Coordination compounds have great importance in biological systems. In this context,which of the following statements is incorrect?

Assign $A, B, C, D$ from the given type of reaction.
$K_4[Fe(CN)_6] + 2CuSO_4 \longrightarrow Cu_2[Fe(CN)_6] \downarrow + 2K_2SO_4$

$A$ solution when treated with dimethyl glyoxime gives a rose red complex. The metal present is

Identify $(A)$ to $(E)$ and also explain the reactions involved.
$CuCO_3 \to CuO$ $\xrightarrow{\text{Heat with } CuS} (A)$ $\xrightarrow{\text{conc. } HNO_3} (B)$ $\xrightarrow{NH_{3(aq)}} (C) \text{ (Blue solution)}$
$CuCO_3 \to (D)$ $\xrightarrow{Ca(OH)_2} (E) \text{ (Milky)}$ $\xrightarrow{CO_2} Ca(HCO_3)_2 \text{ (Clear solution)}$

Which one of the following platinum complexes is used in cancer chemotherapy?