What system integrates multiple services and functionalities into a cohesive structure?

The correct choice is the Enterprise Service Bus (ESB). An ESB is a middleware architecture that enables different services and applications to communicate with one another within an organization. It allows for the integration of various services and functionalities into a single, cohesive framework, facilitating data exchange and service orchestration across disparate systems. By serving as a communication layer, an ESB enhances system interoperability, scalability, and flexibility, making it easier to manage and integrate multiple services seamlessly.

In contrast, while Service-Oriented Architecture (SOA) also aims to promote integration and is a broader architectural style for building distributed systems, it does not specifically denote a single system for interaction like an ESB does; instead, SOA can employ an ESB to achieve its goals. A Configuration Management Database (CMDB) is a system designed to track and manage an organization's IT assets and configuration items, but it doesn't integrate services. A Content Management System (CMS) focuses on creating, managing, and delivering digital content, and is not primarily concerned with integrating multiple services.