Just like the Campeonato Brasileiro, groups from the lessen series, which include B and C, can be promoted to the top division each year. In the case of Italy, only the leading three teams in Serie B are promoted to Serie A (in Brazil, promotion happens for four groups in https://keo-nha-cai65454.blogdeazar.com/37878551/what-is-serie-a-can-be-fun-for-anyone