I don't really know it but I think the answer is following
C. They are usually a low-risk investment.
Thoreau, who believed this poll tax supported the Mexican-American war and the expansion of slavery into the Southwest, had stopped paying this tax in 1842 but the sheriff, Sam Staples, failed to take action against him for several years.
Answer:
c.) hawthorne effect
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.