After the united states declared war on germany, approximately how long did it take for over a million american troops to arrive in europe?
a. two months
b. two years
c. one month
d. one year

The question is asking to states or calculate how long did it take for over a million American troops to arrive in Europe and base on my research and further investigation, the possible answer would be in letter D. One year. I hope you are satisfied with my answer and feel free to ask for more 

D.) One year Because I just took a test on this and made a 100 that's why I say it's D