Answer:
The correct answer is: decrease.
Step-by-step explanation:
The Hawthorne effect was conducted between the 1920s and 1930s by Henry A. Landsberger (born in 1926) in the Western Electric's Hawthorne Works electric company in Chicago, Illinois. After the research, Landsberger concluded that employees' productivity is subject to being observed or not while doing their duties alleging that is the only motivation employees had. The more observed are workers, the higher the productivity.
In the example, Rollin's performance is likely to decrease according to the Hawthorne effect because no motivation factor pushes her to improve her productivity.