I ' ve got it ! I am lifting it , lifting it , almost putting it on the island , almost there , and ... . The cardboard bends AGAIN and now the entire thing falls to the floor AGAIN , but this time from a higher point in the air , so the velocity of the fall smashes it completely .

Question: Why did the structure collapse ?
Answer: None of the above choices .Because the cardboard was in the air .Because the cardboard was wet .Because the spine bent .