Question

A researcher gives a vitamin to half of the subjects in an experiment and a placebo (a pill with no active ingredient made to look like a vitamin) to the other half. The researcher is incorporating what aspect of successful experimental design in his study?
A. blocking
B. self-selection
C. bias
D. control

Answer 1

D control, the researchers are creating a control group that experience all of the same conditions of the test group (receiving a pill) but receive no benefit of the vitamin. It helps to reduce variable in the study to determine validity