Wilkinson's catalyst is the first highly active homogenous hydrogenation catalyst. Then, the chemical name of the catalysts
| A. |
tristriphenylphosphonium iridum chloride |
 |
| B. |
tristriphenylphosphonium cobatlium chloride |
| C. |
tristriphenylphosphonium rhodium chloride |
| D. |
tristriphenylphosphonium cobaltium bronmide |