Question: In a laboratory, a sealed container with 100 g of steam is cooled until all the steam becomes a liquid. The container is then cooled further until all the water becomes a solid. Which of the following remains constant during both of these changes?

  Options: 
 A. the mass of the water
 B. the pressure in the container
 C. the total energy of the water
 D. the position of the atoms in the container
Answer: A