What event provided an opportunity for colonies across the world

The event that provided an opportunity for colonies around the world is Christopher Colombus's exploration of the New World, or the Americas. Here, the Americas provided plenty of natural resources and land, so many European countries decided to set up colonies in order to gather resources. They also used Slaves to work for them.

Explanation:

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the fact that could also be added to column b is that during world war ii, specifically between the years 1941 and 1945, japan expanded its territory towards the indonesian territory in what was known later as part of the "pacific war". in that time, japan could conquer the philipines, singapore,   borneo, central java, malang, cebu, sumatra and various other islands of the area, therefore expanding its territory for a brief period of time.