The appropriate tool to update the firmware for HPE ProLiant MicroServer Gen10 Plus servers is HPE iLO 5. Integrated Lights-Out (iLO) 5 is a powerful management tool that provides the necessary interfaces to perform remote server management tasks, including firmware updates, without requiring physical presence. HPE Composer, HPE Data Services Cloud console, and HPE GreenLake Central serve different purposes and are not specifically designed for firmware updates on these servers.