Comprehensive and Detailed Explanation
When defining the scope of an architecture, TOGAF identifies four dimensions that need to be considered:
Breadth – This dimension addresses the extent of the enterprise that will be impacted by the architecture. It answers the question: How much of the enterprise is covered? For example, does the scope include the entire enterprise, a business unit, a division, or just a single organizational function?
Depth – This refers to the level of detail to be covered. For instance, will the architecture describe high-level capabilities, or will it go into detailed system design?
Time Period – This defines the planning horizon of the architecture. It could be short-term (tactical), medium-term, or long-term (strategic).
Architecture Domains – This refers to which domains are covered: Business, Data, Application, and Technology. The scope may include all or just a subset of these domains.
Project Scope (sometimes discussed separately) – Focuses on which specific programs, portfolios, or projects will be impacted.
Among these, the dimension that specifically relates to the extent of the enterprise is Breadth.
Why the other options are incorrect
A. Architecture Domains: Refers to the domains covered (Business, Data, Application, Technology), not the extent of the enterprise.
B. Depth: Refers to the level of detail, not the enterprise extent.
C. Project: Refers to the program or initiative focus, not enterprise coverage.
References
The Open Group, TOGAF® Standard, Version 9.2, Part II: ADM — Preliminary Phase (scope considerations).
The Open Group, TOGAF® 9 Certified Study Guide — discussion of the dimensions of architecture scope (Breadth, Depth, Time Period, Architecture Domains).