How many casualties were there in world war 1

37 million although some list the number as high as 40 million

Explanation:

World War One was listed as one of the deadliest conflicts in the history of the human race, in which the total number of both civilian and military casualties is estimated at around 37 million people. Many were killed in battle but others were killed by disease, malnutrition and infections.

it was on the rise and doing very well and would continue to do well until the great depression from 1929-1939

c. is the answer : ) (you may punch me if im wrong lol)