Answer:
The correct answer will be option-Test the variation in the amount of amylase produced by each individual before and after being presented with a bowl of pasta.
Step-by-step explanation:
In the given question, the scientist wants to study the increase in the amount of the starch digesting enzyme called amylase after eating the starchy food.
Scientist designed the experiment and measured the amount of amylase of the volunteers after eating the food. But this could lead to the error in the data as the scientist has not measured the initial amount of amylase of each volunteer before eating as the before values can act as a reference and the result values can be compared.
Thus, the selected option is the correct answer.