Final answer:
To increase the rate of a reaction, one should increase both the concentration of reactants and the temperature, which leads to more collisions and forceful interactions, overcoming the activation energy barrier.
Step-by-step explanation:
To increase the rate of a reaction, one could increase the concentration of reactants or increase the temperature. An increase in concentration leads to a higher number of collisions between reactant particles, thus raising the reaction rate. Additionally, raising the temperature of a reaction typically results in a higher reaction rate because the reactant particles move faster and the collisions are more forceful, making it easier to overcome the activation energy barrier for the reaction to occur. Therefore, the correct answer is: a) Increase concentration, Increase temperature.