Why Is It Optimal for a Researcher to Ensure That

question 137

Multiple Choice

Why is it optimal for a researcher to ensure that only one variable changes throughout an experiment?

• A) Because more than one variable creates a statistical nightmare that is exceedingly difficult to interpret.
• B) Because multiple variables will require more research participants, and thus more funding.
• C) Because more than one variable changing can influence our results and lead to incorrect conclusions.
• D) Because the definition of a true experiment is that only one variable should change at a time; otherwise, it is not an experiment.

---

Definitions:

Thrombin

An enzyme in blood plasma that causes the clotting of blood by converting fibrinogen to fibrin.

Systole

Contractile phase of the cardiac cycle.

Diastole

Relaxation phase of the cardiac cycle.

Cardiac Cycle

The sequence of events that occurs in the heart during one heartbeat, including contraction (systole) and relaxation (diastole) of the atria and ventricles.