Which of the following is true of the MAXMINCON principle? A researcher tries to minimize the variance of the variable or variables pertaining to the research questions. A researcher tries to maximize the error variance of random variables due to errors of measurement or individual differences of participants. An experimenter tries to control the variance of extraneous or unwanted variables that might affect or bias the variables in question. An experimenter tries to conduct an investigation in a real-life setting that does not exercise experimental control