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

The correct answer is option a. "bacterium caused the Black Death" Yersinia pestis (also known as Bacillus pestis or Pasteurella pestis), is the patoghenic agent behind the plague of the Black Death. This disease was transmited to humans through the bite of infected rats. The bacteria was described and cultured by Alexandre Yersin in Hong Kong in 1894.

this isn't a question and if you're going to list things be kind and use commas.

b. ensure mutual protection from communism.

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