Which option is essential for successful printing of a mini CC refund receipt?

The successful printing of a mini CC refund receipt relies heavily on using a specific sign on/off. This process is critical because it ensures that the system recognizes the user as properly authenticated to perform the transaction. Without the correct sign on/off, the system may not allow the transaction to process, which could prevent the generation of the refund receipt altogether. This step typically includes entering the correct credentials or following set protocols that are part of the system's operational guidelines.

The other options do not directly address the mechanics of printing a receipt. Changing membership type does not pertain to the printing process itself and is more related to account management. Contacting customer service is typically a follow-up action for issues outside the immediate scope of printing and would not resolve a transactional issue on the spot. Ensuring printer functionality is important for overall printing tasks but does not specifically relate to the sign on/off process that governs access to perform refunds.