Answer:
Option D, How is the molecular arrangement of liquid water different from the molecular arrangement of solid water?
Step-by-step explanation:
Nancy found that density of water decreases when it is frozen. Since density of any substance depends on its molecular arrangement , it is very essential to understand the difference between the molecular arrangement of liquid and solid water.
Hence, a question that investigate the above stated fact shall be the most logical and right question to reach a scientific explanation of the difference in density observed by Nancy.
Hence, option D is correct.