According to the PMBOK Guide, 6th edition, section 6.2.2.4, the project manager should use agile practices such as sprint reviews and retrospectives to ensure that the product backlog items are delivered according to the product owner's expectations and that the team continuously improves its performance. Sprint reviews are meetings where the team demonstrates the product increment to the product owner and other stakeholders and collects feedback for future iterations. Retrospectives are meetings where the team reflects on its processes, tools, interactions, and outcomes and identifies areas for improvement. These practices help to align the team and the product owner on the project vision, scope, and quality, and to prevent or resolve any issues or conflicts that may arise during the project. The PMI-PBA Guide, section 5.2.3.1, also supports this approach, as it states that the business analyst should participate in sprint reviews and retrospectives to validate the requirements and to ensure that the product meets the business needs and stakeholder expectations.
References:
* PMBOK Guide, 6th edition, section 6.2.2.4
* PMI-PBA Guide, section 5.2.3.1