Actually every single one is correct, A<B<C they all are factors in the decline of Sumer.
Answer:
a.The guns made it easier for troops to gain ground rapidly and fearlessly by crossing trenches.
Explanation:
The machine gun revolutionized combat endeavors and rapidly drove out countries with their horse-drawn carriages into submission. From its uncovered roots beginnings to the advancement of this notable weapon that is still being used today, it figured out how to practically without any assistance change the result of WWI and along these lines change the craft of war.
Answer is in the photo. I can't attach it here, but I uploaded it to a file hosting. link below! Good Luck!
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