What must a player do to legally serve the ball?

To legally serve the ball, a player must serve from anywhere behind the end line. This rule is essential because it allows for a clear starting point for the serve, ensuring that all players are in their designated positions and that the serve is done from a proper area designated by the rules. Serving from behind the end line also allows the player to have a running start if they choose, maximizing their serving potential and strategy.

In contrast, jumping while serving is not a requirement; players can choose to serve with or without jumping. Letting the ball bounce before hitting it is not a legal requirement for a serve in volleyball, as the player must strike the ball cleanly from their hand or toss it into the air. Additionally, serving while standing on the court is not permissible, as players must remain behind the end line during the serve. These guidelines ensure fairness and consistency in the game.