The answer is letter A, the year 1953.
Created as part of the Korean Armistice Agreement between North Korea, the People’s Republic of China and the United Nations Command forces, the Korean Demilitarized Zone between North Korea and South Korea or most commonly known as the DMZ was established on July 27, 1953, in which it has remained fully functional ever since. One of the most heavily militarized areas in the world, the Korean Demilitarized Zone was intended to demarcate North Korea from South Korea.
