How does the IT4IT Reference Architecture use the value stream concept?

How does the IT4IT Reference Architecture use the value stream concept?
A . As a way of grouping functionality to provide context for where value is being created and delivered
B . To support predictable, sequential, waterfall approaches to IT service delivery
C . As a macro-process and capability architecture to provide context for IT value delivery and operations
D . In order to be compliant with the Value Chain concept of Michael Porter

Answer: A