Read the passage carefully and answer the questions.

The coordination compounds are of great importance. These compounds are widely present in the mineral, plants and animal world and are known to play many important functions in the area of analytical chemistry, metallurgy, biological systems, industry and medicine. For example, coordination compounds find use in many qualitative and quantitative chemical analysis. Some important metal extraction and purification make use of complex formation. Hardness of water can be estimated by stable complex formation of $ \text{Ca}^{2+}$ and $\text{Mg}^{2+} $

Wilkinson catalyst used for hydrogenation of alkenes is a complex of ……………

Rhodium

The correct answer is Option (3) → Rhodium

Wilkinson's catalyst = Rhodium Complex used in homogeneous catalytic hydrogenation of alkenes.