Answer:
The correct word for the blank space is: the human side of motivation.
Explanation:
Henry A. Landsberger (born in 1926) held observational experiments at the Hawthrone Works Chicago -a Western Electric factory, after which he concluded that humans beings change their behavior when they are being observed. The Hawthrone effect also implies talking about individuals' motivation in the framework that could take the company to optimal production levels.
