Which is an example of a heterogeneous catalyst?
a amylase

b catalytic converter

c food preservatives

d amino acids

b.catalytic converter is correct option.

Explanation:

Heterogeneous catalysts: In this catalyst phase is different from the phase of the reactants. In heterogeneous catalysis, reactants are in the gas phase and solid phase catalysts are involved.The catalytic converter is a example of heterogeneous catalysts,In which palladium, rhodium are used as hetrogenous catalysts.The catalytic converter is used to decrease the toxic gases with the process of a redox reaction.The catalytic converter uses a catalyst to carry the reaction. The catalytic converter used in gasoline is the example of heterogeneous catalysis.catalytic converter by oxidation process converts the carbon monoxide gas into carbon dioxide.

That would be 'unbalanced.' Hope it helps!