Which of the following Combatant Commands has the support of NATO as one of its missions?

U.S. European Command is the correct choice because it directly operates in collaboration with NATO and is designed to bolster security and defense in Europe. NATO (North Atlantic Treaty Organization) is primarily focused on the defense of its member nations in the North Atlantic area, and U.S. European Command plays a significant role in coordinating U.S. military efforts in this theater, including ensuring the collective defense of NATO allies.

The essential function of U.S. European Command includes not only fostering military readiness but also enhancing interoperability with NATO forces during various operations and exercises. The close alignment of European Command’s objectives with NATO's collective security interests highlights the importance of NATO support as a foundational element of its mission.

In contrast, U.S. Northern Command, U.S. Southern Command, and U.S. Central Command primarily focus on different geographic areas and missions that do not inherently involve NATO’s framework or collective security as their core responsibilities. U.S. Northern Command focuses on domestic defense in North America, U.S. Southern Command concentrates on South America and the Caribbean, and U.S. Central Command is primarily focused on operations in the Middle East and parts of South Asia. Thus, these commands do not have NATO collaboration as a defining aspect of their missions.