Probably 1, however I can see why that would be a tiny bit confusing.
Building walls protects from incoming invaders(at least back in the day), creating armies, makes a force to go and fight to protect the people, and what was the other one? Oh yea, moving to a safer place.
Doing that would mean making invasions less likely, and making your people feel and be safer.
Hope this helps.
Answer: In 1917, Germany, determined to win its war of attrition against the Allies, announced the resumption of unrestricted warfare in war-zone waters. Three days later, the United States broke diplomatic relations with Germany, and just hours after that the American liner Housatonic was sunk by a German U-boat.
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where are the answer choices
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