A team is drawing an opportunity solution tree for the first time. What belongs at the top, and what do the branches immediately beneath it hold?

The principle — the tree is read downward, from what the team wants to achieve to the needs that could get it there.

Why the key is correct — Torres describes the tree as Opportunity solution trees are a simple way of visually representing the paths you might take to reach a desired outcome. The desired outcome is the root, and the branches beneath it are These are the customer needs, pain points, and desires that, if addressed, will drive your desired outcome. Solutions hang below those, so every solution on the diagram is attached to the need it serves. The Scrum Guide describes the same shape at the top: The Product Goal describes a future state of the product which can serve as a target for the Scrum Team to plan against.

Why the others are wrong — a feature at the top turns the whole diagram into an implementation plan and removes the question the tree is for. Grouping existing solutions into themes builds upward from decisions already taken, which produces a diagram that can only confirm them. And ranking the branches replaces a map of the paths available with an ordering, which is a later and different decision.

Remember this — outcome at the top, needs beneath it, solutions beneath those.

Sources — Teresa Torres on opportunity solution trees, Product Talk; the 2020 Scrum Guide.