Final answer:
The Arizona Territory was formed from the region that previously belonged to New Mexico. It was ready to become a state by 1912 after a series of negotiations over its borders and governance. Option c is the correct answer.
Step-by-step explanation:
Formation of the Arizona Territory
The Arizona Territory was formed from the region previously belonging to New Mexico after the land was acquired by the United States from Mexico. Following the signing of the Treaty of Guadalupe Hidalgo in 1848, which ended the Mexican-American War, the U.S. gained a large portion of what is now the American Southwest, including present-day Arizona.
Arizona was carving out its identity and governance within the union, preparing itself for statehood. It was not until 1912 that Arizona was officially admitted into the United States as a state. The journey towards statehood was long and complex, involving negotiations over territorial borders, issues relating to the institution of slavery, and the establishment of a state government.
During America's period of expansion, westward movement and the concept of Manifest Destiny were primary forces shaping policy and territorial acquisition. The independent Republic of Texas, the subsequent annexation threatening the balance of free and slave states, and the resulting compromises - all played critical roles in how the map of the United States was drawn, leading up to and past the Mexican Cession.