Explanation
Based on the TOGAF standard, this answer is the best approach for architecture development to realize the CEO's change in direction for the company. The reason is as follows:
The scenario describes a major business transformation that requires a clear understanding of the current and future states of the enterprise, as well as the gaps and opportunities for change. Therefore, the priority is to understand and bring structure to the definition of the change, rather than focusing on the implementation details or the technology aspects.
The team should use the TOGAF ADM as the method and guiding framework for architecture development, and adapt it to suit the specific needs and context of the enterprise. The team should also leverage the existing Architecture Capability and the Architecture Repository to reuse and integrate relevant architecture assets and resources.
The team should focus iteration cycles on a baseline first approach to architecture development, which means starting with the definition of the Baseline Architecture in each domain (Business, Data, Application, and Technology), and then defining the Target Architecture in each domain. This will help to identify the current and desired states of the enterprise, and to perform a gap analysis to determine what needs to change in order to achieve the business goals and objectives.
The team should then focus on transition planning, which involves identifying and prioritizing the work packages, projects, and activities that will deliver the change. The team should also create an Architecture Roadmap and an Implementation and Migration Plan that will guide the execution and governance of the change.
The team should use the Architecture Vision phase and the Requirements Management phase to work out in detail what the shared vision is for the change, and to capture and validate the stakeholder requirements and expectations. The team should also use the Architecture Governance framework to ensure the quality, consistency, and compliance of the architecture work.
References: : The TOGAF Standard, Version 9.2 - Architecture Development Method : The TOGAF Standard, Version 9.2 - Architecture Vision : The TOGAF Standard, Version 9.2 - Requirements Management : [The TOGAF Standard, Version 9.2 - Architecture Governance]

Architects should review and consolidate the gap analysis results from Phases B to This will identify the transformations required to achieve the proposed Target Architecture. The Enterprise Architects should then assess the readiness of the organization to undergo change and determine an overall direction to address and mitigate risks identified. The Transition Architecture should then be planned to use a state evolution table.
Explanation:
The Business Transformation Readiness Assessment is a technique that can be used to evaluate the readiness of the organization to undergo change and to identify the actions needed to increase the likelihood of a successful business transformation. This technique can help to address the concerns of the key stakeholders about the risks and value of the proposed reorganization. The technique involves assessing the following aspects of the organization: vision, commitment, capacity, capability, culture, and communication. Based on the assessment, the risks associated with the transformations can be identified, classified, and mitigated for. The technique also helps to identify the dependencies between the set of changes, including gaps and work packages, and the improvement actions to be worked into the Implementation and Migration Plan. The technique also supports the determination of the business value, effort, and risk associated for each transformation, which can be used to prioritize and sequence the work packages and the Transition Architectures1 Reference: 1: The TOGAF Standard, Version 9.2, Part III: ADM Guidelines and Techniques, Chapter 27: Business Transformation Readiness Assessment

The TOGAF standard covers the development of four architecture domains: Business, Data, Technology and Application. These domains represent different aspects of an enterprise's architecture and provide a consistent way of describing, analyzing, and designing them. Reference: The TOGAF Standard | The Open Group Website, Section 2.2 Architecture Development Method (ADM).

Explanation
The phase of the ADM labeled as item 1 is Phase F: Migration Planning. This phase conducts implementation planning for the architecture defined in previous phases by creating an Architecture Roadmap and a detailed Implementation and Migration Plan. This phase also identifies and groups major work packages, transition architectures, projects, and dependencies. References:
https://pubs.opengroup.org/architecture/togaf9-doc/arch/chap19.html

The Business Transformation Readiness Assessment technique is used to evaluate the readiness of the organization to undergo change and to identify the actions needed to increase the likelihood of a successful business transformation. These actions should be incorporated in the Implementation and Migration Plan, which is the detailed plan to transition from the Baseline Architecture to the Target Architecture. The Implementation and Migration Plan also includes the Transition Architectures, the Architecture Building Blocks, the Work Packages, the Implementation Governance Model, and the Architecture Contract12 Reference: 1: The TOGAF Standard, Version 9.2, Part III: ADM Guidelines and Techniques, Chapter 27: Business Transformation Readiness Assessment 2: The TOGAF Standard, Version 9.2, Part II: Architecture Development Method (ADM), Chapter 21: Phase F: Migration Planning