Which option is NOT a typical control technique for extraneous variables?

• A. Randomization
• B. Standardization
• C. Counterbalancing
• D. Increasing sample size dramatically

Answer: (D)

When designing an experiment, extraneous variables threaten internal validity by potentially influencing the dependent variable alongside the manipulation. The strategies used to control these variables aim to make groups as comparable as possible and keep procedures consistent. Randomization distributes individual differences evenly across conditions, so any unknown extraneous factors don’t systematically bias the results. Standardization ensures every participant experiences the same procedures, instructions, and environment, reducing differences that could affect outcomes. Counterbalancing is used in within-subject or repeated-measures designs to vary the order of conditions, preventing order or sequence effects from confounding the results. Increasing sample size dramatically, while it improves statistical power and the precision of estimates, does not directly control extraneous variables and thus is not a typical method for handling them.