Answer: Increasing the amount of sugar.
Explanation: Increasing the amount of reactants increases the rate of the reaction. This is given by the collision theory, which states that a chemical reaction must involve the collisions of particles together, as well as with the walls of the container it is in. By increasing the amount of reactant in the container you are increasing the collision frequency, and the rate of the reaction is dependant on the collision frequency multiplied by the fraction of collisions that are effective. Increasing the temperature increases the collision frequency as well as the fractions of collisions that are effective, so it’s definitely not that one. Hope this helped:)