Three sensory conditions (no noise, moderate noise, loud noise) illustrate what aspect of the experimental design?

• A. Independent variable levels
• B. Dependent variable levels
• C. Baseline measures
• D. Debriefing

Answer: (A)

The key idea is that the researcher is deliberately changing a factor to see its effect on an outcome. The three sensory conditions—no noise, moderate noise, and loud noise—are different values of that manipulated factor, so they represent the levels of the independent variable. The thing you measure to see the effect (for example, task performance or reaction time under each noise level) is the dependent variable. Baseline measures are data collected before the manipulation to establish a starting point and aren’t levels of the manipulated factor. Debriefing happens after the experiment and isn’t part of the design manipulation.