When does a throw-in become live?

A throw-in becomes live when it is at the thrower's disposal. This means that the player taking the throw-in has received the ball from the official and is ready to begin play. The crucial part of this situation is that the ball is not considered live until the throw-in situation is properly established, which includes the player being in the correct position, the ball being handed over, and any relevant reasons for the throw-in being fulfilled.

Once the thrower has the ball in their hands, they must be in a position to make the throw-in, and it's only at that moment the ball is officially in the process of being put into play. This is consistent with the rules of basketball, ensuring that all players are aware and ready for the game resuming. In contrast, the other options suggest moments that either do not fully represent the process of the throw-in being established or imply that play has started prematurely.