Variables Are Said to Be Confounded When ________

Variables are said to be confounded when ________.

A) each participant has an equal chance of being assigned to each experimental condition
B) a factor that is not systematically varied exists and may have an effect on an experiment's outcomes
C) an experiment includes too many factors for the researcher to control in a laboratory
D) each participant will experience all experimental conditions at different times
E) participants are randomly assigned to experimental conditions