Final answer:
The "one-drop rule" was a classification system used in American history to determine a person's race based on their ancestry. Anyone with even a small amount of African or black ancestry was considered black, while those with European ancestry were treated as white.
Step-by-step explanation:
The "one-drop rule" refers to a classification system that was used in American history to determine a person's race based on their ancestry. According to this rule, anyone with even a small amount of African or black ancestry, ranging from 1/8 to 1/32 or even a known trace, was considered to be black and treated accordingly. The one drop of African or black blood was seen as enough to categorize a person as non-white, regardless of their appearance or social status. On the other hand, if a person could prove that they had at least "one drop" of European blood, they would be treated as white.
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