Which of the following experimental designs would allow a researcher to determine the effect of mycorrhizae on plant growth?
A) measure and compare the growth of two different plants that both have mycorrhizae associated with their roots
B) measure and compare the growth of two different plants, one of which has had antifungal substances added to it and one that has not
C) measure and compare the growth of two different plants that do not have mycorrhizae associated with their roots
D) measure and compare the growth of two different plants, one of which has had antibiotics have been added to it and one that has not

Question

Quizplus · Accepted Answer

To determine the effect of mycorrhizae on plant growth, comparing the growth of a plant with antifungal substances (which would inhibit mycorrhizae) to a plant without such substances allows for direct observation of mycorrhizae's impact.

Which of the Following Experimental Designs Would Allow a Researcher