d
The \(IUPAC\) name of \(K _2\left[ Cr ( CN )_2 O _2\left( O _2\right) NH _3\right]\) is Potassium amminedicyanodioxoperoxo chromate \((VI)\).The cation is potassium and the anion is the complex ion containing chromium metal in \(+6\) oxidation state.
The oxidation state is written in roman numerals inside parenthesis.
The ligands \(O\) and \(O _2\) are oxo and peroxo respectively.
The prefix di indicates two.