please specify the source of the question.
as for the question, the PMBOK guide states that Validate Scope is the process of formalizing acceptance of the completed project deliverables. The PMBOK guide also states that The verified deliverables obtained from the Control Quality process are reviewed with the customer or sponsor to ensure that they are completed satisfactorily and have received formal acceptance of the deliverables by the customer or sponsor.
as you said the customer is involved in defining the acceptance criteria and for sure the customer must be involved in the acceptance of the final deliverable to ensure the acceptance criteria are met and as for the project you will need a formal sign off and acceptance from the customer.
Moderators: Yolanda Mabutas, Ahmed Amin, Scott Gillard, Mary Kathrine Padua, ERIC BARTLETT, Gail Freedman, Kevin Nason, Steven Mudrinich, PMP, Mark Wuenscher, PMP, John Wolverton, Tracy Shagnea, PMP, Jada Garrett
This interview with Simona Fallavollita (LinkedIn Profile) was recorded at the magnificient Project Management Institute (PMI)® Global Conference 2017 in Chicago, Illinois. We discuss the how, what, why and when of the changes that are coming to the PMP exam.