Answer: The manor system offered people protection.
In the manor system, peasants will be allowed to work in a land that belonged to the certain lord and require the peasants to make some contributions from the result of their works.
As a return, the Lord will provide knights to protect everyone that live in that land, including the peasants.
In a classroom of 20 students, it would most likely be a "direct democracy" that makes the most sense, since the relatively small number of students means it would be easy to calculate the votes on various issues.
Less terroristic attacks.
The great dying and columbian exchange.