For iterating over items in a retail application, which step page is best suited for modification of unit prices?

The best choice for modifying unit prices during iteration over items in a retail application is the DiscountItems.pxResults step page. This page specifically contains the results of a data transform or a reporting operation that reflects the items to be processed.

When dealing with iterated operations in Pega, especially in cases where you're modifying properties like unit prices, it is essential to work with the most relevant context. The DiscountItems.pxResults step page directly represents the items retrieved for the appropriate iteration and allows changes to be made to the relevant properties of those items.

In contrast, the other options either do not give the necessary context for the specific items being processed or refer to broader pages that might not have direct access to the properties needing modification. For instance, DiscountItems could represent a broader context, whereas ItemList might not be focused on just those results, and ResultsPage could imply a different usage scenario altogether. Thus, using the DiscountItems.pxResults step page is the most effective and appropriate method for modifying unit prices directly associated with the items that are currently being iterated.