When an <<*AskOptions. . .*>> block is answered during a document assembly session, Pathagoras assigns and records the positional value of the selected item(s) to the !GroupName! of the equation. Pathagoras then creates a new set of !GroupNames! and implicitly assigns a 'True' (or 'False') value to each selected (or not selected) value. (The !GroupNames! created carry the exact names of the <<*AskOptions . . .>> choices. This allows you to insert an <<*Optional*!groupname!* . . . >> in the document body.
See this page for more information and examples.