Question

jenna is testing how high blood sugar levels affect athletic performance. which variable is the independent variable? blood sugar level, because it is manipulated by jenna athletic performance, because it is measured by jenna blood sugar level, because it is measured by jenna athletic performance, because it is manipulated by jenna

Explanation:

In an experiment, the independent variable is the one that is deliberately changed or manipulated by the experimenter. Here, Jenna is manipulating blood - sugar levels to see its effect on athletic performance.

Answer:

Blood sugar level, because it is manipulated by Jenna