正解:D
CX portfolio consists of five service categories that cover the entire lifecycle of a technology:
Support Services: Provide technical support, software updates, and smart capabilities to help customers maintain network availability, security, and performance Business Critical Services: Provide expert guidance, best practices, proactive support, and insights to help customers optimize their network performance, security, and availability Professional Services: Provide consulting, design, implementation, integration, optimization, and migration services to help customers deploy and adopt Cisco solutions Managed Services: Provide end-to-end management, monitoring, and operation of customer's network infrastructure and applications by Cisco or certified partners Learning Services: Provide training, certification, and enablement programs to help customers develop their skills and capabilities on Cisco technologies