A catalyst lowers the activation energy from $20 \mathrm{kJ} {\mathrm{mol}}^{-1}$to $15 \mathrm{kJ} {\mathrm{mol}}^{-1}$ of the forward direction of the reaction $\mathrm{A}\rightleftharpoons \mathrm{B}$. Which of the following statement regarding the reaction is correct?

Activation energy of the backward direction is increased by $5 \mathrm{kJ} {\mathrm{mol}}^{-1}$

Activation energy of the backward direction is decreased by $5 \mathrm{kJ} {\mathrm{mol}}^{-1}$

Enthalpy ofreaction is increased by $5 \mathrm{kJ} {\mathrm{mol}}^{-1}$

Equilibrium constant of the reaction is decreased