Which of the Following Is TRUE of Experiments

Multiple Choice

Which of the following is TRUE of experiments?

A) An experiment has greater ability to supply evidence of causality because it takes longer to complete than a descriptive study.
B) Researchers have more control when performing experiments than they have when using exploratory or descriptive designs.
C) External validity is more important to determine than internal validity.
D) An experimental design is a research design in which the investigator has direct control over at least one independent variable and manipulates at least one dependent variable.
E) Both b and d are true.