Japanese Americans were transported under military guard to 17 temporary assembly centers located at racetracks, fairgrounds, and similar facilities in Washington, Oregon, California, and Arizona. <u>Then they were moved to one of 10 hastily built relocation centers. By November 1942 the relocation was complete. </u>
The answer is: B) The relocation centers were hastily built.
After Pearl Harbor attack in World War II all the Japanese Americans were sent to Manzanar, the were incarcerated in this concentration camp, all the ten concentration camps were built hastily in order to relocate all of them fast under the request made by President Franklin D. Roosevelt in order to avoid anyone who might threaten the war effort.