Zeynep: I filled a balloon with air. The balloon changed shape when I squeezed it.
Emre: That's because air is a gas. Its particles are far apart and move freely.
Zeynep: So, gases don't have a fixed shape or volume.
Which of the following is TRUE according to the conversation?
A)Gases have a fixed shape.
B)Gases have a fixed volume.
C)Gases have particles that are tightly packed.
D)Gases can change both shape and volume.