What expansion option displays every member under a given parent in a Cube View?

The option that displays every member under a given parent in a Cube View is correctly identified as "Descendants." When you choose the Descendants option, it reveals all the child members associated with the selected parent member throughout the hierarchy. This means that every level of data that falls under that parent is fully expanded and shown, providing a comprehensive view of the structure beneath the parent node.

In contrast, the other options function differently. The Hierarchical View typically provides a visual representation of the members and their relationships but may not necessarily display every member under the parent in an expanded format. The All Members option would show every member in the cube but does not focus specifically on a parent-child relationship, potentially leading to a more cluttered view that lacks contextual organization under a specific parent. The Siblings option highlights only the members that share the same parent, failing to provide context on deeper levels of the hierarchy associated with the selected parent. Thus, Descendants is the most appropriate choice for displaying every member beneath a specified parent.