In an experiment, a researcher prepares a reaction mixture by dissolving a substance in a buffered solution. The substance is the substrate of a certain enzyme. The researcher adds a small amount of the enzyme to the reaction mixture and measures the amount of product that is formed over time. Which of the following best predicts the immediate result of adding more substrate to the reaction mixture at the point indicated by the arrow in Figure 1?

answer choices
The amount of product will decrease until the reaction rate goes to zero.
The amount of product will increase until the reaction reaches its equilibrium point or until the substrate is used up by the reaction.
The amount of product will increase without stopping because the enzyme will be unchanged by the reaction.
The amount of product will decrease until the reaction reaches its equilibrium point or until the enzyme is been used up by the reaction