What is the primary responsibility of the referee during a match?

The primary responsibility of the referee during a match is to enforce the laws of the game. This encompasses ensuring that the match is conducted fairly and according to established rules, which includes monitoring player conduct, assessing fouls and infractions, and deciding when to apply disciplinary measures. The referee must be knowledgeable about the rules and consistently apply them to maintain the integrity of the match.

Options like keeping track of time, managing the score, and maintaining player fitness are indeed important aspects of officiating, but these fall secondary to the overarching duty to enforce the laws effectively. The enforcement of the laws impacts the flow and fairness of the game, making it the referee's essential function during the match.