Task: Text Categorization
Input (English): The Keo Nua Pass in this country is one of the few passes through the Annamese Cordillera (CORE-dee-YARE-uh). This nation's capital includes the Temple of the Trung Sisters and is located on the Red River. The imperial citadel of Dai Noi is found in this country's onetime capital Hue (hway). For 10 points, name this Southeast Asian nation that was reunified in 1975 after a bloody war between the communist north and U.S.-aligned south.
Output (English): Social Science