Which statement characterizes experimental research?

• A. Historical research
• B. Evaluation research
• C. Experimental research
• D. Exploratory research

Answer: (C)

Experimental research is defined by actively manipulating an independent variable and observing the effect on a dependent variable under controlled conditions, with random assignment and a control or comparison group to isolate the cause-and-effect relationship. This setup aims to demonstrate causality by minimizing confounding factors and ensuring that observed effects are due to the manipulation. Other types—historical research uses past data with no manipulation, evaluation research assesses programs often with non-experimental designs, and exploratory research seeks to generate hypotheses rather than test causal relationships—do not establish causality in the same controlled way. So the statement that highlights manipulating variables with a controlled design and randomization best characterizes experimental research.