Kellogg's is running a field experiment to determine how much effect prices have on their cereal sales. However, the prices of competitors' cereals is an extraneous factor that must be accounted for. Fortunately, Kellog's can identify and measure all of their competitors' prices so that they can use _______________ to control this extraneous factor. Kellogg's is running a field experiment to determine how much effect prices have on their cereal sales. However, the prices of competitors' cereals is an extraneous factor that must be accounted for. Fortunately, Kellog's can identify and measure all of their competitors' prices so that they can use _______________ to control this extraneous factor. design control physical control matching randomization statistical control