Which research method is best suited to establish causal relationships?

• A. Correlational studies.
• B. Observational studies.
• C. Experimental studies.
• D. Survey research.

Answer: (C)

To establish causal relationships, you need evidence that changing one factor leads to a change in another, while ruling out alternative explanations. Experimental studies are best for this because they involve deliberate manipulation of an independent variable and random assignment of participants to different conditions. This setup controls for extraneous factors, so differences in the outcome can be attributed to the manipulated cause. The sequence is also controlled so the cause comes before the effect, which establishes temporal precedence. Including a comparison or control group strengthens the conclusion that the observed effect is due to the manipulation.

Correlational studies, in contrast, measure relationships between variables as they occur naturally and can show that two things move together, but they cannot determine which causes which, or rule out third variables. Observational studies involve watching behavior without manipulating conditions, which similarly limits causal inferences. Survey research often yields correlational data from self-reports and thus shares the same limitation unless it's designed in a way that addresses directionality and confounds.

So, the experimental approach is the one that most effectively supports claims about causality.