Considering how hantaviruses are transmitted to humans, what conclusion can MOST likely be made from the fact that it has been found all over the world? Options:

-Rodents live in all parts of the world, giving hantavirus a carrier in which to spread.

-Pigs have become used in most diets around the world, causing ingestion of hantavirus to rise.

-Monkeys were once only found in tropical or sub-Saharan climates but are now kept in zoos or even as pets.

-Dogs, although man's best friend, can shed the virus without showing any symptoms at all.