The Bubonic plague was spread by * a. an overall drop in temperatures known as a “little ice age.”
B. poisoned water from the town wells.
C. the Great Famine.
D. rats infested with fleas carrying the bacterium.

D

Explanation:

A is not right, because it wasnt temps!

b is the wrong disease (that was cholera!)

the great famine is also wrong.. that was in ireland with potatoes i think?

and d is right!!! it was spread by rats in europe and asia in like the 1200's.

answer; people where able to travel across the u.s.a faster than any other mode of transportation,travel time was about a week,from coast to coast

they wanted the u.s. to fight on the side of the central powers.