The deadliest pandemic in recorded history by percentage of global population is the Black Death, which killed about one-third of Europe's population in the 14th century. While the Spanish flu had a high death toll, it affected a smaller percentage of the global population. Thus, the Black Death stands out as the deadliest pandemic in history. ;
The Black Death is the deadliest pandemic in recorded history, significantly affecting one-third of Europe’s population in the 14th century. The Spanish flu had a high death toll but represented a smaller percentage of the global population. Therefore, the correct answer is the Black Death.
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