Refer to the figure.

-The figure is based on Johnson's experiment on the effects of trematode parasites on tadpoles. Which statement best describes the control group in the experiment?
A) Tadpoles were grown in the absence of trematode parasites.
B) Tadpoles were allowed to grow in nets in their natural environment.
C) Tadpoles were grown in the presence of only one trematode parasite.
D) Tadpoles were grown in a tank in which the concentration of trematode parasites was similar to the parasite concentration of ponds in which deformed frogs were found.

Question

Refer to the figure.
 
-The figure is based on Johnson's experiment on the effects of trematode parasites on tadpoles. Which statement best describes the control group in the experiment?
A) Tadpoles were grown in the absence of trematode parasites. 
B) Tadpoles were allowed to grow in nets in their natural environment. 
C) Tadpoles were grown in the presence of only one trematode parasite. 
D) Tadpoles were grown in a tank in which the concentration of trematode parasites was similar to the parasite concentration of ponds in which deformed frogs were found.

Quizplus · Accepted Answer

The control group in an experiment is the group that does not receive the experimental treatment, which in this case is the presence of trematode parasites.

Refer to the Figure