Explanation:

This answer states that defining the acceptance criteria is what the BA should do next after conducting discovery sessions for implementing Experience Cloud at UC and writing user stories. Acceptance criteria are a set of conditions or tests that a user story must meet or pass in order to be considered done and ready for deployment or delivery. Defining the acceptance criteria means that the BA specifies what the solution must do or have to satisfy the user story, and how to verify or measure its success. Defining the acceptance criteria is what the BA should do next after writing user stories because it helps the BA to clarify and communicate the requirements and expectations of the user story, and to ensure that the solution meets them.