Which definition best describes the staff training service component within the wireless implementphase？（）

A、develops a training plan and delivers via a custom workshop or e-learning

B、helps improve the performance and functionality of the infrastructure operations and networkmanagement system

C、reduces the risk of downtime caused by facilities-related problems

D、provides a step-by-step plan detailing the installation and service-commission requirementtasks to bestaged in a controlled implementation environment that emulates a customer network