Duplicated systems are those in which:

The concept of duplicated systems refers to a structure where development takes place at the central or home base, and then those developed systems are handed over to operational units located in foreign regions. This approach typically ensures that the core technology, processes, and systems are standardized at the home base, allowing for uniformity and control over the primary functionalities.

By centralizing the development, the home base can leverage its expertise and resources to create robust systems that can then be adapted or utilized by foreign units, which may operate autonomously but still rely on the foundational work done at headquarters. This can facilitate efficiency, reduce redundancy in system development, and ensure that all units are operating on a shared framework.

In contrast, the other choices reflect different organizational structures or philosophies. The model of foreign units designing their own unique solutions implies a lack of centralization and control that characterizes duplicated systems. Integrated and coordinated operations across units suggest a fully collaborative model rather than one where development is centralized. Lastly, having foreign units design the solutions used domestically contradicts the nature of duplication, which seeks to standardize solutions from the home base down to foreign operations. Thus, the unique structure of duplicated systems is highlighted by the collaboration between a central development hub and autonomous operational branches.