The correct answer is option-1, Dresden Line. The Dresden Line is not an international boundary line.

Option-2, Durand Line, is a well-known international boundary line between Afghanistan and Pakistan. It was established in 1893 by the British when they controlled the region. The Durand Line has been a source of tension and conflict between Afghanistan and Pakistan.

Option-3, Maginot Line, was a system of fortifications built by France in the 1930s to defend against potential German aggression. It stretched along the French border with Germany and Luxembourg, and while it did not prevent the German invasion in World War II, it is still considered an international boundary line.

Option-4, 38th Parallel, is the boundary line separating North Korea and South Korea. It was established in 1945 after World War II and has since been a heavily militarized zone.

Therefore, only option-1, Dresden Line, does not exist as an international boundary line.