Answer:
D. Frames
Explanation:
An animation is made up of individual images called FRAMES.
The term refers to old film ribbons where each image was presented in a frame, on the long film ribbon that would be moving in front of a light to project the movie images.
A. Thumbnails: they're a small version of an image.
B. Hot spots are areas that can be clicked to link somewhere else for example.
C. Icons are small images, can be animated or not.
