Answer: The amount of reactant doesn't really affect the rate of reaction, but the concentration does.
In order for there to be a reaction there has to be collisions between molecules, but only a fraction of these collisions are successful. The molecules have to be moving with enough energy, called the activation energy, to break the bonds between atoms. If there is a higher concentration of a solution, there are more molecules present per unit volume. This means that there will be more collisions and therefore more successful collisions, increasing the rate of reaction.
Step-by-step explanation:
B