In the 1340's, the black death spread to europe as a result of what human interaction

 The Black Death (bubonic plague) spread to Europe as a result of TRADE -- specifically, merchant ship contacts between Europe and regions to the east where the disease had originated.

Context/details:

The History Channel gives this report of the coming of the Black Death to Europe from the Central Asia region:  

The disease spread to Europe and killed more than a third of the continent's population.   Fleas on rats that were on board the ships are usually blamed for the spread of the plague -- though new research suggests the transmission of disease-infected lice from person to person was more likely the main cause of the pandemic.

A recent paper published in the Proceedings of the National Academy of Science has cast much doubt on the idea that rats were the primary cause of the Black Death's spread. A team of researchers from the universities of Oslo and Ferrara have concluded that the spread of the disease mostly occurred due to lice and fleas on human hosts (not rats). Prof. Nils Stenseth, from the University of Oslo said: “The conclusion was very clear. The lice model fits best. ... It would be unlikely to spread as fast as it did if it was transmitted by rats.  It would have to go through this extra loop of the rats, rather than being spread from person to person.” (Quoted in January 16, 2018 article in The Independent.)

Ultimately, the spread of the plague occurred the way communicable diseases typically spread.  With any communicable disease, which is spread by communicating (moving) from one person to another, as long as there was some form of contact then the disease could spread.

post the grid otherwise i cant .

also it sounds like a math question not history.

        i'm fairly sure that the correct answers are 2 and 3.

        i used both my knowledge of world history and the process of elimination to obtain these answers. option 1 cannot be a possible selection because the mandate of heaven belongs to ancient chinese philosophical belief. option 4 sounds like it would benefit the region than detriment it. however, both 2 and 3 explain a potential reason for what could have contributed to the fall of the roman empire.

      hope this ! if i were you, i'd get a second opinion, because i haven't taken this course for a year. best of luck!

***websites that me understand the curriculum better last year are and ***