The music played during the earliest films (pre-1900) a. conveyed the mood of each scene. b. was played on a phonograph. c. introduced characters and themes. d. covered the sound of noisy projectors.

The correct answer is option A. Conveyed the mood of each scene.

The phonograph was not used to play sound on films until the beggining of the 20th century. Instead, a group of musicians would be brought along with film presentations, as well as a "rancoteur" - a person who would explain the actions and themes of the film to the audiences. The primary purpose of live music during films was to set the mood in accordance the events on screen.