Final answer:
Early movie theaters, such as nickelodeons, were never truly silent because they featured live musical accompaniment to enhance the viewing experience. Projectors made noise too, but the live music was a deliberate and expected part of the silent film experience.
Step-by-step explanation:
Early movie theaters, like nickelodeons, were never really silent when playing silent movies because A) Live musical accompaniment was often provided. This accompaniment could include a pianist, organist, or even a small orchestra, depending on the venue's size and resources. These musicians played music synchronized with the action on screen to enhance the audience's experience and compensate for the lack of recorded dialogue and sound effects. Audiences expected this musical dimension as part of the cinematic experience, which was also applied in other forms of entertainment at the time, such as vaudeville.
Another reason the theaters weren't silent was B) The projectors made loud mechanical noises, which also contributed to the overall noise level in the theater. However, the primary reason was the live music that was used to provide emotional and dramatic context to the films. C) Audiences were encouraged to talk during screenings is not true, as the norm was to watch movies quietly, which is a tradition that continues today. And finally, D) Sound effects were added in post-production is incorrect for silent films as they had no synchronized recorded sound to begin with.