B.5.2.0:4.3 - Boundary rule

Only a declared prompt species carrying an explanatory question enters B.5.2 through this form. For a choice among available probes, actions or specialist options, use C.11. Use C.38 to develop incomplete alternatives for the same intended result, C.11.DUA to examine an unclear evidence demand, and C.19 when the question is policy over a still-live candidate pool. C.18 records generation and comparison results; C.22.1 describes an adaptation signature. Neither performs the missing choice. An explanatory subquestion arising during planning can still enter B.5.2 on its own grounds.