To determine which event happened third in the sequence, let's break down the timeline provided in the last paragraph:
- Audiences watched the early movies in silence because the movies had no sound. (This is the first event mentioned.)
- Theater owners hired piano players to play music during screenings of silent movies. (This follows as the second event after audiences initially watched in silence.)
- Piano players invited audiences to sing along to the music when the movie reels were being changed. (This is the third event that takes place as an extension of having piano players in the theaters.)
Based on this analysis, the correct answer is:
B (Piano players invited audiences to sing along to the music when the movie reels were being changed.)