The correct answer is letter B
The Black Death was a pandemic, that is, the widespread proliferation of a disease caused by the bacillus Yersinia pestis, which occurred in the second half of the 14th century, in Europe. This plague was part of the series of events that contributed to the Crisis of the Lower Middle Ages, such as the peasant revolts, the Hundred Years War and the decline of medieval cavalry.
The Black Death has its origin in the Asian continent, precisely in China. Its arrival in Europe is related to the commercial caravans that came from Asia across the Mediterranean Sea and arrived in European coastal cities, such as Venice and Genoa. It is estimated that about a third of the European population has been decimated because of the plague.
The disease spread, initially, through rats and, mainly, fleas infected with the bacillus, which ended up being transmitted to people when they were bitten by fleas - in whose digestive system the plague bacteria multiplied. At a more advanced stage, the disease began to spread by air, through sneezing and droplets. The precarious conditions of hygiene and housing that medieval towns and villages contributed to the spread of the disease - which offered conditions for the infestation of rats and fleas.
The war was fought because America was built upon slavery. During the Industrial Age, the northern economy no longer needed slavery. The south however was wasn’t ready nor was trying as hard to give up its dependency on slavery. The south economy would plummet and life for southerners would drastically make a down spiral if they couldn’t have access to expensive but efficient workers you never had to pay for.
