<h3>Consequences of soil erosion</h3>
Soil erosion decreases agricultural productivity, degrades ecosystem functions, amplifies hydrogeological risk such as landslides or floods, causes significant losses in biodiversity, damage to urban infrastructure and, in severe cases, leads to displacement of human populations.
Answer: In Medieval Europe, knights pledged loyalty to vassals, who in turn pledged theirs to powerful lords, and serfs labored in the fields.
Explanation:
A rigid hierarchy refers to one where people who are born into a certain position in life, find it quite hard to move from it or rather one where there are different social classes and people had to be classified in one class for the system to work.
The system during medieval times was much like this. Social classes existed that determined a person's worth in society such as the knights, vassals, Lords and Royals. There was also the serfs who were considered the lowest in the hierarchy.
The correct answer among the choices presented above is the fourth option. Magnetic minerals are a part of molten rock at mid-ocean ridges. Examples are chromite, magnetite, limenite and ferberite. Hope this answers the question.
