The correct option is C True
Transition metals are more efficient catalyst as they have vacant d- orbitals. The ability of transition metals to form more than one stable oxidation state means that they can accept and lose electrons easily. This enables them to catalyze certain redox reactions. They can be readily oxidized and reduced again, or reduced and then oxidized again, as a consequence of having a number of different oxidation states of similar stability. They can behave either as homogeneous catalysts or as heterogeneous catalysts.