An organization that adopted agile a few years ago wants a more efficient way to ensure each sprint increment meets end users' quality requirements. What should the project lead recommend?

Developing a more comprehensive Definition of Done (DoD) directly addresses the need for ensuring quality requirements are met. The DoD defines the criteria that a product increment must satisfy to be considered complete, including quality standards. By making it more comprehensive, the team explicitly outlines and agrees upon all necessary quality checks, leading to higher-quality increments. Establishing a separate QA team can create a bottleneck and goes against agile principles of cross-functional teams and built-in quality. Holding more frequent sprint reviews might identify issues sooner but doesn't inherently improve the quality of the increment itself. Increasing testing effort is good, but without a clear definition of what quality means (as provided by the DoD), it might not target the right aspects or be consistently applied.