The correct option is B decreases
∙ A catalyst is a substance that alter the rate of a reaction without undergoing any chemical change itself.
∙ Catalysts alter the reaction rates by providing an alternate pathway for the reactants to form products.
∙ A negative catalyst decreases the rate of reaction by increasing the activation energy of the reaction.
∙ However, a positive catalyst decreases the activation energy of the reaction and thus, increases the rate of reaction.