Plan from the supplied facts
Original graph arrows mean “provides input to”: A→B, B→C, A→D. Assume a changed node can affect all reachable consumers. The affected set includes the changed node itself. This is an impact-search model; a reachable node still needs its actual change reviewed.
| Changed node | Immediate consumers | Full candidate set |
|---|---|---|
| A | B,D | A,B,C,D |
| B | C | B,C |
| C | None | C |
Work through the choice
C can be missed when only A’s direct arrows are read. Conversely, changing B does not reach sibling D or upstream A under this directed model.
If D changes, which nodes enter the candidate impact set?
Show the worked answer
D only. It has no outgoing edge in the supplied graph, so no downstream node is reachable.
Material to use in your plan
Keep directed input edges and a visited-node set. Traverse outgoing edges from the changed node until no new nodes remain, then review each candidate’s real dependency.