I believe the answer is: It was weakened and could not provide military protection.
Land reclamation refers to the process of creating new land by elevating the land that covered by the sea or lake and extracting the water out.
Due to the large budget for this project, the government have less money to be allocated for military supplies and soldiers.
United States bombing Nagasaki
Answer C.
The kingdom of Mali of West Africa controlled trade routes which had previously been controlled by the kingdom of Ghana.
With the demise of Ghana the Mali empire arose in West Africa taken all the trade routes left by Ghana.
