Question

new evidence changed ideas about what caused the black death when a team of scientists visiting hong kong discovered that
a bacterium caused the black death.
a virus caused the black death.
rabies caused the black death.
tetanus caused the black death.

Explanation:

The Black Death, also known as the plague, is caused by the bacterium Yersinia pestis. This bacterium is transmitted through fleas that infest rodents.

Answer:

a bacterium caused the Black Death.