Which of the following complexes is likely to exhibit geometric isomerism?
Correct: C
Geometric isomerism occurs when atoms or groups of atoms are arranged differently in space around a central metal ion, and this is possible when there are at least two different ligands. Tetrahedral (like Zn and often Ag) and linear complexes generally do not exhibit geometric isomerism due to the free rotation of ligands. [Co(NH₃)₅Cl]²⁺ cannot exhibit geometric isomerism due to having multiple of the same ligand. Square planar complexes with the general formula MA₂B₂ (like trans-[Pt(NH₃)₂Cl₂] ) exhibit cis-trans isomerism (geometric isomerism).