After an injury, what is one of the actions a coach has 30 seconds to complete?

In the context of volleyball, after an injury to a player, coaches have specific responsibilities to ensure the game continues smoothly while prioritizing player safety. One of those responsibilities is to complete a legal libero replacement.

The libero is a specialized defensive player who has distinct rules regarding substitution with other players on the team. If a libero needs to be replaced due to injury, the coach is allowed a limited time frame to notify the officials and execute this substitution. This action must be conducted within the 30-second window to maintain the flow of the game and adhere to the rules set forth by governing bodies like NFHS.

The other options, while they may be actions a coach could consider, do not have a specific requirement linked to the 30-second injury period. Adjusting strategies or calling timeouts could be valid responses in broader contexts of a game, but they are not bound to the quick response needed for an injured player. Substituting any player for the injured player is also not permitted as it must be a libero specific substitution when dealing with that role. Therefore, executing a legal libero replacement is the crucial action that must be taken promptly within that limited timeframe.