How did the great wall of china earn its spot on the "7 wonders of the world" list?

Built between the 5th century B.C. and the 16th century, the Great Wall of China is a stone-and-earth fortification created to protect the borders of the Chinese Empire from invading Mongols. The Great Wall is actually a succession of multiple walls spanning approximately 4,000 miles, making it the world's longest manmade structure.

I hope this helps. :p

  The question is asking for you to look at the different types of art forms in your life, like fashion, architecture, or material arts, then state how that form of art is unique and innovative, then compare it to Walt Whitman's work. 

All i did was rephrase the question for you, but i hope its easier to understand, because i think the original question used "innovative" too much, that always confuses me.