The Senate was the most powerful branch of the Roman republic, and senators held the position for life. The executive branch was made up of two consuls, elected yearly. These two consuls had almost kingly powers, and each could veto, or disapprove of the other's decision.
It is letter A the Mongols.
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and fyi i am Turkish.<span />
Answer:
C. Trench warfare
Explanation:
A's incorrect as alliances have existed for thousands of years
B's incorrect as an infantry charge's greatest weakness is the machine gun for obvious reasons
D's incorrect as both sides had machine guns, and was not the reason for victory.
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This leaves C, which makes sense as troops would be forced to hide on lower ground due to the deadliness of machine guns
(2) devolved advanced architectural techniques