Historians label an event as a turning point when it
A. Affects more than on region of the world
B. Marks a major social, economic,or political shift
C. Cannot be categorize into existing historical themes
D.occurs multiple times during different historical periods.
For example, in World War II, the turning point was when Hitler began to fall out of power as the other countries (the US, Britain, Russia) started to gain more and more power over him and Germany.