There was a need for cheaper routes along the Mediterranean and the east was becoming tumultuous.
The event that got the USA seriously involved with WW2 was the attack on Pearl Harbor on December 7, 1941.
I believe the answer is A. 5
Abundance of resources = trade/cooperation
Scarcity of resources = conflicts
The more resources you have the more likely a civilization was to get along with those around it, although at the same time if the civilization was weak and had a lot of resources it would be at risk of invasion/attack.
