A scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected. The rate of the reaction could also be determined by measuring the change in the amount of enzyme Answer A: measuring the change in the amount of enzyme A measuring the change in the amount of substrate Answer B: measuring the change in the amount of substrate B measuring the change in salt concentration Answer C: measuring the change in salt concentration C adding more substrate Answer D: adding more substrate D adding more enzyme