Explanation
The organization should follow the approach of creating one value stream for the entire project, to enable an end-to-end, holistic vision of the service. A value stream is a series of steps that an organization undertakes to create and deliver products and services to consumers. A value stream should cover the whole service value chain, from the demand to the value delivery. Creating one value stream for the entire project helps to ensure that the service is aligned with the customer needs, expectations, and outcomes, and that the value is co-created by the provider and the consumer. Creating one value stream also helps to identify the value, waste, and opportunities for improvement in each step, and to optimize the service delivery process. The other options are not correct, as they would result in fragmented, incomplete, or inconsistent value streams. Creating separate value streams for practices, people, tools and suppliers would not consider the 'four dimensions' equally, but rather isolate them from each other. Creating separate value streams for every project phase would not ensure that each milestone is achieved in an Agile manner, but rather create gaps and delays between the phases. Creating one value stream for each team would not allow the teams to focus on their different objectives, but rather create silos and conflicts among the teams. References:
ITIL 4 & swarming - finding the right people & process | Axelos1
Swarming vs Tiered Support Models Explained - BMC Software2
What ITSM Practitioners Need to Know About Value Stream Mapping3
ITIL 4 Value Streams: do the right things for customer | Axelos4