Answer: Earth reinforcing
Explanation: Earth reinforcing is a method of strengthening the soil/ground when constructing foundation by combining materials such as steel or concrete to the soil. It is especially useful for the construction of conventional retaining walls or mining structures.
Historically, steel nets were used on areas with soft clay, such as sea beds. Some materials used now include Geonets and geogrids.
A) increasing trade with the Europeans
B) desire to make a religious pilgrimage to Mecca
C) improved transportation infrastructure
D) rise of the middle class that could afford leisure travel
