I believe it is either A. or C. my guess is A.
Because they do not have the same qualities therefore they are different
You can take two liquids of different densities (how much mass is in a given volume) and pour them into a funnel. An example is oil and water. When the mixture settles, the denser liquid will be at the bottom, and drips through the funnel first. This is a separation that you can just let occur naturally.
The correct answer is the last option. When <span>Zac releases the air from a balloon, it will expand to fill the room. It will not expand in the sense that molecules will be big but the molecules will be more spread out into the room and more air molecules will be present to fill the room.</span>