Dr. Lee is interested in the effect of lighting on people’s ability to concentrate. Dr. Lee studies this by manipulating the amount of lighting while participants read and then measuring their scores on a reading comprehension test. Group 1 receives dim light, and group 2 receives bright light. Which of the following research methods is Dr. Lee using? a. A case study b. A survey c. A correlational study d. An experiment e. A simulation

Experimental research: An experimental research is defined as the research method that is strictly coherent to the scientific research design. In an experimental research design, there is a hypothesis involved, and different variables in which one variable is being manipulated by the researcher and the other variable is being measured, compared, and calculate. The experimental research is being completed or calculated in a strictly controlled environment.

In the question above, Dr. Lee is using the experimental research method.