<span>Mali
</span><span>Congo
</span><span>Aksum
Kush
Luba
</span><span>Nubia</span>
A)a new defensive tactic known as trench warfare
Trench warfare allowed the war to drag on for long periods of time because of the stalemates that ensue from the opposing armies refusing to give up the land under their controls, resulting in high casualties in no man's land.
Hope this helps
The answer is "Pope Urban II"
