Explanation
User experience in production should be excluded from the testing scope for User Acceptance Testing. User Acceptance Testing is a phase of testing that involves end users validating the functionality and usability of the solution in a sandbox environment that mimics the production environment. User Acceptance Testing should not include testing user experience in production, because this can affect live data and operations, and introduce errors or risks. Large data volumes, data load simulation, and average versus peak performance should be included in the testing scope for User Acceptance Testing, because they can help evaluate the performance and scalability of the solution under different scenarios and conditions. References:
https://trailhead.salesforce.com/en/content/learn/modules/application-lifecycle-and-development-models/te
https://www.salesforce.org/wp-content/uploads/2019/03/Education_Cloud_COE_Guide.pdf