What is the 49th state of the United States?

Alaska holds the distinction of being the 49th state admitted to the United States, officially joining the Union on January 3, 1959. It was the first state to be admitted after World War II, following the earlier admissions of Arizona and New Mexico in 1912. The significance of Alaska's geographic size and natural resources has made it an important part of the United States, influencing both economic and strategic aspects of national policy.

The other options represent states that were admitted to the Union at different times. Hawaii is the 50th state, having been admitted later in 1959. Arizona was the 48th state, joining in 1912, and New Mexico also achieved statehood the same year as Arizona. Understanding the sequence of state admissions is crucial in grasping the history of the United States' expansion and development.