Value chain analysis technique

Question $11$ options:

Analyzes the chain of activities extending from the ultimate source of supply to the end user in order to understand the activities and processes performed, the behavior of costs, and sources for potential competitive advantage.

is used within a firm's internal value chain or key processes.

Currently very limited$,$ largely between immediate supplier and customer with information shared limited to the costs pertaining to a joint project.

All of the above are correct

only a and b are correct.