Correct option is A
Antenna Function: The antenna indicates whether the ball has crossed the net within the legal boundaries of the court.
International Standards: The FIVB (Federation Internationale de Volleyball) specifies the colors and dimensions for volleyball court equipment, including the antenna.
The antenna is usually attached to the top of the volleyball net and extends vertically from it.
The visibility of the antenna is crucial for players, referees, and spectators to determine whether the ball is in-bounds or out.