Final answer:
The sentence "By bringing the characters to the big screen, the movie makes an impression" most clearly describes the medium of a story, indicating a movie is the format through which the story is told.
Step-by-step explanation:
The sentence that most clearly describes the medium of a story is: "By bringing the characters to the big screen, the movie makes an impression." This sentence indicates that the medium through which the story is told is a movie, which is a different format from a book, play, or other forms of storytelling. The medium affects how the audience perceives and engages with the story, providing sensory details beyond text, and often making a story more powerful by leveraging visual and auditory elements.