is an extensive body of law issued by state or federal agencies to direct the enacted laws of the federal or state government

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

answer; dead end or culdesac;

answer; environmental science;