Answer:
c.) hawthorne effect
Step-by-step explanation:
The Hawthorne effect is regarded as the phenomenon in which the subjects in behavioral studies tend to change their performance in response to being observed.
It is always counter productive in terms of result because it is hard to study when results are biased, the participants knew they were being studied.
Due to the individuals knowledge that they are being studied, most times it produces not exactly the result it should.