From the textbook research design By ALAN E. Kazdin: How is controlling for other independent variables different from holding conditions constant? a. Controlling for other independent variables is a technique that removes the statistical impact of these variables. b. Controlling for independent variables ensures standardized intervention procedures are followed. c. Controlling for other independent variables means removing any and every variable that could affect the dependent variable. d. Controlling for other independent variables means including only subjects who had similar upbringings