According to PMBOK 6, the project manager can find the agreed-upon risk response strategy from the Risk Register and the Risk Report (pg448). For exam purpose, if the Risk Response Plan Document is shown in one of the answer choices, it would be an incorrect answer.
That being said, I would like to think that standalone risk response plans would not be uncommon in real-world projects, especially when the risk responses are elaborate and complex.
Does the risk response plan exist as a document itself? Some sources refer to it as an existing document to review but the official outputs from Risk response planning from PMBOOK are update for project management plan, update for risk register and change requests.