Which equipment must be padded in volleyball?

The correct choice identifies the equipment that must be padded to ensure player safety during a volleyball match. Standards, net support floor/wall cables, and the referee platform need padding to minimize the risk of injury. When players are diving for the ball or engaging in fast-paced play, they may inadvertently collude with these fixed structures. Padding these elements helps absorb impact and protects players from potential harm, aligning with safety regulations outlined in the NFHS guidelines.

Other options pertain to equipment that either doesn't pose the same level of risk or is not specifically required to be padded. The net and ball, for example, are essential for gameplay but do not pose a physical hazard that requires padding. Similarly, while the referee platform may be padded alone, it is more comprehensive to include all specified equipment as necessary for padding.