Much like the Campeonato Brasileiro, teams during the lower series, which include B and C, might be promoted to the top division annually. In the case of Italy, just the top 3 teams in Serie B are promoted to Serie A (in Brazil, advertising takes place for 4 teams in https://rylanlgyrj.nizarblog.com/37885795/the-smart-trick-of-what-is-serie-a-that-nobody-is-discussing