A Researcher Is Studying Absorption Rates of Natural and Synthetic

A researcher is studying absorption rates of natural and synthetic vitamins. The researcher has three groups of randomly assigned subjects: one group that will receive the natural vitamin, one group that will receive the synthetic vitamin, and a control group that will receive a placebo. Which type of quantitative design is the researcher using?

A) Experimental design
B) Quasi-experimental design
C) Nonexperimental design
D) Meta-analysis