Exam OG0-092 topic 1 question 20 discussion

Scenario:
You have been assigned the role of Chief Enterprise Architect within a leading North American information technology services company. The company has a number of service portfolios including infrastructure, applications, business process outsourcing, accounting, and financial services.
With numerous practice areas and a multitude of diverse engagements underway at any given time, overall engagement management within the company has become challenging. The company does not want to risk its outstanding reputation or its international certifications and CMM ratings.
The Chief Executive Officer and Chief Information Officer have co-sponsored the creation of an Enterprise Architecture prog-am based on TOGAF 9. An
Architecture Board has been formed comprised of IT staff executives and executives from the major practice areas.
The Enterprise Architecture team has been working with the Strategic Planning team to create a strategic enterprise architecture to address these issues. The team has defined a framework and held workshops with key stakeholders to define a set of architecture principles to govern the architecture work. They have completed an Architecture Vision at a strategic level and laid out Architecture Definitions for the four domains. They have set out an ambitious vision of the future of the company over a five-year period. This includes a solution architecture including three distinct transformations.
The CIO has made it clear that prior to the approval of the detailed Implementation and Migration plan, the EA team will need to assess the risks associated with the proposed architecture. He has received concerns from some of the senior partners that the proposed architecture may be too ambitious and they are not sure it can produce sufficient value to warrant the attendant risks.
You have been asked to recommend an approach to satisfy these concerns.
Based on TOGAF 9, which of the following is the best answer?