Answer:
the answer is A because it was in the earliest period of time though out all of them
The most deadly illness the pioneers have faced was Oregon Trail, it was spread by for hunting food, picking berries, and most of all this terrible game kids used to play that made them realize the Oregon Trail was real. It also lead up to bad fever, cholera, and dysentery.
This is the main reason of the deadly illness pioneers had.
Hope this helps you :)
B because more powerful weapons on one side leading to less power to the opposing side
