Researchers attempt to rule out possible biasing effects of extraneous variables by using the following two types of control

A) random assignment of participants and experimental control
B) experimental control and within-subjects control
C) random assignment of participants and statistical control
D) experimental control and statistical control

Random assignment of participants helps ensure that any potential extraneous variables are evenly distributed across all experimental conditions, reducing their potential to bias the results. Experimental control involves manipulating only the independent variable(s) and keeping all other variables constant to isolate the effect of the independent variable on the dependent variable.