The case of the extraneous variable is most likely to be determined by the student grade level that is level of the education program that is for the grade level. This refers to all the course level and can be use to trace out the external variable that are not intentionally studied in the test or experiment and tends to affect the other variables.
Wihelm Wundt founded experimental psychology as a discipline and became a pioneer of cultural psychology. He created a broad research programmed in empirical psychology and developed a system of philosophy and ethics from the basic concepts of his psychology – bringing together several disciplines in one person
