Answer :
(1) D. Fighting in the Easter Front was mobile, while the Western Front devolved into a stalemate because of the use of trench warfare.
(2) C. U-boat attacks destroyed convoy ships and hampered supply lines, which affected the armies' ability to adequately feed and supply their soldiers.
(3) A. Poison gas was a innovation used by the Germans to try to break the stalemate on the Western Front. After the war it was forbidden.
Final answer:
The key differences between the Eastern and Western Fronts were their mobility; the U-boats' primary impact was the destruction of vital supplies; and poison gas, responsible for many deaths, was banned after World War I.
Explanation:
The Eastern and Western Fronts of World War I were distinct theaters of war with different patterns of combat. In particular, the answer to question (1), which asks about differences between the Eastern Front and the Western Front, is D: The Eastern Front had front lines that moved widely, while the Western Front did not. This is because the Eastern Front, which consisted of the German, Russian, and Austrian armies, was highly mobile compared to the static trench warfare that characterized the Western Front.
Regarding question (2), concerning the effect of U-boat attacks, the most significant impact was C: They destroyed vital supplies. U-boat attacks targeted supply routes, leading to the loss of essential materials and resources needed by armies on the land.
In question (3), the type of warfare responsible for civilian and military deaths and later banned was A: poison gas. Poison gas was used during World War I as a lethal weapon that inflicted horrendous injuries and death, leading to it being prohibited in future warfare.
