In an experiment designed to test the effect of temperature on goldfish respiration, the temperatures that were changed represent what type of variable?

A. control

B. responding

C. experimental

D. correlative

E. placebo

C. experimental

Explanation:

Experimental variables are the variables that are changed during the experiments to observe the effects of these changes. An experiment usually has one or more experimental variables. An experimental variable that is changed to know its impact on some other variable is called the independent variable.

In the given experiment, goldfishes were exposed to various temperature conditions to observe the effect of temperature on respiration. Therefore, both temperature and respiration rate are the experimental variables here.