Final answer:
The Black Death is caused by the bacterium Yersinia pestis.
Step-by-step explanation:
The disease known as the Black Death, which still sporadically appears today, leads to the development of buboes in individuals bitten by infected fleas and is caused by the bacterium Yersinia pestis.
The Black Death, also known as the Bubonic Plague, was one of the deadliest pandemics in human history. It swept through Europe in the 14th century and had profound and far-reaching effects on the continent's population and society.