Which of the following is paramagnetic [AFMC 1997]

• A. \[\left[ Ni{{\left( CO \right)}_{4}} \right]\]\[\]
• B. \[{{[Co{{(N{{H}_{3}})}_{6}}]}^{3+}}\]
• C. \[{{\left[ Ni{{\left( CN \right)}_{4}} \right]}^{2-}}\]
• D. \[{{\left[ NiC{{l}_{4}} \right]}^{2-}}\]