Which change in reaction conditions increases both the collision rate and the proportion of molecules with sufficient energy to react?
A
addition of a catalyst
B
increasing the concentration of a reactant
с
increasing the surface area of a reactant
Dincreasing the temperature of the reaction

increasing the concentration of a reactant

Explanation:

Increasing the concentration of one or more reactants will often increase the rate of reaction. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period.

I hope it will help u dear

the answers would be

the first one and the second one

the answer is symmetrical : )