If you wanted to test if antibacterial soap worked better than regular soap, which experiment below has the strongest experimental design?

A. Have two groups of people wash with either antibacterial or regular soap, without knowing which type of soap they are using.
B. Have two groups of people wash with either antibacterial or regular soap.
C. Have people wash with antibacterial soap first and later with regular soap.
D. Have two groups of people wash with either antibacterial or regular soap, with neither the researchers nor the groups knowing which type of soap they are using.


Answer: D

Biology & Microbiology

You might also like to view...

When you drink a large volume of water, the release of ____ by the pituitary gland ____

a. aldosterone; increases b. aldosterone; decreases c. ADH; increases d. ADH; decreases e. ANP; increases

Biology & Microbiology

________ proposed that polypeptides and RNA evolved simultaneously.

A. Graham Cairns-Smith B. Aleksander Oparin C. Thomas Cech D. Stanley Miller E. Sidney Fox

Biology & Microbiology

Most of the dry weight of a plant is the result of uptake of

a) CO2 through stoma. b) water and minerals through mycorrhizae. c) CO2 and O2 through stomata in leaves. d) carbohydrates in the root hairs and concentration in the root cortex. e) water and minerals through root hairs.

Biology & Microbiology

Long nephron loops correlate with

A) urine isotonic to the blood. B) more concentrated urine. C) urine with glucose in it. D) urine hypotonic to the blood. E) more dilute urine.

Biology & Microbiology