The correct answer is number 2) Cold War confrontations.
Unfortunately, you forgot to attach the map. Where is the map?
Without the map, just you know the information. We don't.
However, trying to help you we did some deep research and found one map that highlights places where the United States and the Soviet Union had conflicts and confrontations during the Cold War years.
The places highlighted on the map are the Island of Cuba, North and South Korea, and North and South Vietnam.
So the correct answer indeed is:
A historian could best use this map to study the topic "Cold War confrontations."
During the tense years of the Cold War, the Soviet Union and the United States competed in the arms race, the space race, and the spread/containment of Communism in different places of the world such as the Island of Cuba Korea Vietnam.
the 19th amendment, passed in 1920
