What country developed the open door policy a) china b) the united states c) britain d) germany

I wish I could say B) United States, cos we make bizarre names like that but no, not this time, this time it was none other thatA) China

Explanation: I remember taking stuff like this in class

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

its c