Among $\left(a\right)-\left(d\right),$ the complexes that can show geometrical isomerism are:
$\left(a\right)$ ${\left[Pt{\left(N{H}_3\right)}_{3}Cl\right]}^{+}$
$\left(b\right)$ ${\left[Pt\left(N{H}_3\right)C{l}_5\right]}^{-}$
$\left(c\right)$ $\left[Pt{\left(N{H}_3\right)}_{2}Cl\left(N{O}_2\right)\right]$
$\left(d\right)$ ${\left[Pt{\left(N{H}_3\right)}_{4}ClBr\right]}^{2+}$

• A

  $b$ and $c$
• B

  $d$ and $a$
• Correct answer
  C

  $c$ and $d$
• D

  $a$ and $b$

Hence, the correct answer is option: 'C'.