Based on the fact that leprosy spread across several nations, we can say that A. The bacterium caused a pandemic.
This refers to when a disease that was an epidemic, spreads to other continents or to a larger area.
Leprosy spread from China (Asia) to Egypt (Africa) and Western Europe. This means that the bacterium that caused it, caused a pandemic.
Find out more on pandemics at https://brainly.com/question/19491082.
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