It is the League of Nations
the origin of the human species appears in africa
Hitler and his army were the reason for the holocaust.
Answer:
Option: d. advanced the cause of a southern route for the transcontinental railroad.
Explanation:
In 1853, James Gadsden bought a strip of land from Mexican for $10 million. The Gadsden Purchase was a treaty in which the United States got some land from Mexico present Arizona and New Mexico. The purpose of this land was to build a railroad to California called the southern transcontinental railroad.