At the start of a new Agile development project, the Universal Containers' product owner asked...

This answer chooses user stories as the element that the BA should use to define the intended results of the work based on stakeholder needs. User stories are short and simple descriptions of a feature or a functionality from the perspective of an end user or a stakeholder. User stories can help the BA define what stakeholders want to accomplish, why they want to accomplish it, and how they will measure success. User stories can also help the development and implementation teams to plan product decisions based on stakeholder value. References: https://trailhead.salesforce.com/en/content/learn/modules/salesforce-business-analyst-quick-look/use-user-stories-to-capture-requirements