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
B. They left carvings behind.
Explanation
What remains of their architecture and art, including stone carvings and inscriptions on their buildings and monuments.
Answer:
Passed on March 11, 1941, this act set up a system that would allow the United States to lend or lease war supplies to any nation deemed "vital to the defense of the United States."
Explanation:
Answer: it was probably the most important black revolutionary leader in Americas, revolutionnary leader in Haiti (French colony). This leader of Haitian revolution became later governor of Saint Domingue (name of Haiti at that time).
Explanation: in Haiti revolution started in 1791 and was initiated as a consequence of revolutionary movement in France. Touissant L´Ouverture was in the head of revolutionary movement already at that time. The revolution was not only against French imperialism but it was also revolution of blacks against their white "seigneurs"