In the Designing and Implementing Enterprise Network Assurance (300-445 ENNA) architecture, the deployment of ThousandEyes Enterprise Agents on switching infrastructure is designed to be highly flexible, catering to different management styles and network scales. Modern Cisco switches, specifically the Catalyst 9300 and 9400 Series , support the execution of containerized applications directly on the switch ' s hardware through the Cisco IOS XE Application Hosting framework. 1

Application Hosting (Option A) refers to the manual method using the Cisco IOS XE Command Line Interface (CLI). An engineer can use app-hosting commands to install, configure, and manage the Docker-based Enterprise Agent. 2 This provides granular control over resource allocation and networking for the container. Catalyst Center (Option B) provides a GUI-driven, automated workflow to deploy agents at scale across an entire campus fabric. 3 It simplifies the lifecycle management by handling the installation and activation across multiple switches simultaneously. For switches acting as edge devices in an SD-WAN fabric, Catalyst SD-WAN Manager (Option C) orchestrates the deployment through centralized policies and templates, allowing the agent to be pushed as part of a device configuration. Finally, while the ThousandEyes Portal (Option D) is the management plane for tests, it is also where the Docker image and Account Group Token are obtained for any of the aforementioned deployment methods.

Each method provides the same end result: an Enterprise Agent running " on-box " to provide deep visibility into the network path starting directly from the access or core layer. Therefore, All of the above (Option E) is the correct answer as it encompasses the manual, automated, and orchestrated methods available for switch-based deployment as per the 300-445 ENNA official guidelines.