What is the purpose of the libero jersey in volleyball?

The purpose of the libero jersey in volleyball is primarily to identify a player who has specific roles and restrictions on the court, particularly the rule that they cannot attack the ball above the net from anywhere outside the 10-foot line. The libero is a defensive specialist and wears a different colored jersey to easily distinguish them from other players on the team. This differentiation helps officials and spectators recognize the player’s role in the match, especially since the libero can substitute in and out of the game without counting against regular substitution limits.

The other options do not accurately represent the role of the libero. For example, while the libero may serve in certain situations, this is not the defining purpose of the jersey. Additionally, the libero's jersey is not meant to signify a team captain or blocking specialist. Therefore, the unique attributes associated with the libero jersey are crucial for understanding their function and restrictions during gameplay.