Aresearcher designs an experiment to investigate the effect of environmental temperature on the function of an enzyme. for each trial included in the experiment, the researcher will add the enzyme and its substrate to an aqueous buffer solution and then measure the amount of product formed over 20 minutes.
which of the following must remain the same for all trials in this experiment?

a. the initial concentration of the substrate
b. the final concentration of the product
c. the three-dimensional structure of the enzyme
d. the temperature of the aqueous buffer solution

The initial concentration of the substrate must remain the same for all trials in this experiment.

CONSTANT VARIABLE:

In an experiment, there are two variables to watch out for. They include the independent and dependent variables. The independent variable is the variable that is changed by the experimenter and this is the different temperature used for the enzyme in this case. The dependent variable is the variable that is measured and this is the amount of product formed by the enzyme. However, there is another variable that must be kept constant for all groups in an experiment. This variable is called constant variable. The constant variable must remain the same for all groups of the experiment in order not to affect the outcome of the tested variable. In this experiment, the constant variable that must remain the same for all trials of the experiment is the initial concentration of the substrate.

Learn more: link

The answer is telescope.