The correct answer is C. Experimental research.
In experimental research, a controlled group condition is used to compare the effects of an intervention on a group of people who receive the intervention (the experimental group) to the effects of the intervention on a group of people who do not receive the intervention (the control group). This allows researchers to determine whether the intervention is effective.
Survey research is a type of research that involves collecting data from a sample of people through surveys. Surveys can be used to collect data on a variety of topics, such as demographics, attitudes, and behaviors. However, surveys cannot be used to determine cause and effect, as there is no control group.
Historical research is a type of research that involves studying the past. Historical research can be used to learn about events, people, and ideas that have occurred in the past. However, historical research cannot be used to determine cause and effect, as there is no control group.
Descriptive research is a type of research that involves describing the characteristics of a group of people or a situation. Descriptive research can be used to learn about the prevalence of a problem, the characteristics of a population, or the relationship between two variables. However, descriptive research cannot be used to determine cause and effect, as there is no control group.