Which of the Following Was the Reason for Congress to Organize

Multiple Choice

Which of the following was the reason for Congress to organize Oregon as a formal American territory?

A) The killing of most of the Native Americans in Oregon
B) The settling of a border along the 49th parallel
C) The killing of fourteen settlers by a group of Cayuse Indians
D) The discovery of gold in this territory
E) The British deciding to move out of this territory