Final answer:
The spread of the bubonic plague followed trade routes, human migration, and poor sanitation in cities.
Step-by-step explanation:
The bubonic plague, also known as the Black Death, spread in a specific route due to various factors. One major factor was trade routes, as infected rats and fleas hitched rides on trade ships and caravans, allowing the disease to spread across different regions. Another factor was human migration, as people who were infected unknowingly carried the disease with them as they traveled to new areas. Lastly, poor sanitation and hygiene practices in cities contributed to the rapid spread of the plague.
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