Substances which alter the velocity of a reaction by mere presence, without undergoing any change in mass and compossition are termed catalyst and the phenomenon is known as catalysis
According to the adsorption theroy of catalysis, the rate of reaction increases because

Options

A. According to the activation energy of the reaction.
B. Concentration of reactant molecules at the active centres of the catalyst becomes high due to adsorption.
C. Adsorption increases the activation energy of the reaction.
D. Adsorption decreases the activation of the energy of the reaction.

Answer

B