Final answer:
The statement that a majority of teachers, firefighters, and police are represented by public-sector unions is true, with specific unions representing each of these groups of public employees.
Step-by-step explanation:
The question, a majority of teachers, firefighters, and police are represented by public-sector unions, is a statement that can be considered true. Public-sector unions indeed represent a substantial portion of these professions. These unions negotiate labor contracts and work conditions for their members, which include teachers, police officers, and firefighters. For instance, the National Education Association (NEA) and American Federation of Teachers (AFT) represent teachers, while the International Association of Fire Fighters (IAFF) and Fraternal Order of Police (FOP) are known to advocate for firefighters and police officers respectively.