In order to prevent the researcher's expectations from influencing study participants, a(an) design is used

Double-blind

Explanation:

A double-blind study is a study in which neither the participants nor the experimenters know who the control group is. This is done in order to prevent the researcher's expectations from influencing the study participants. In this type of experiment, the researchers do not know who is receiving a placebo, so their bias is taken out of the equation.

if it is a supervisor that collects all the handmade products the word is you but if it goes straight to the machine made activity there isn't any word unless there is robot programmed to say you.

answer; i believe the correct answer is prefrontal cortex;