Setting up rate limits to control the number of requests to the Metadata API Setting up rate limits for the Metadata API is essential to manage the load on the Tableau Server and to prevent abuse of the API. Rate limiting helps to maintain the server's performance and stability by controlling the number and frequency of requests processed by the Metadata API. Option A is incorrect because regularly changing the API key, while a good security practice, is not specifically related to the performance and security of the Metadata API in operation. Option C is incorrect as running the Metadata API on a separate server is not a standard requirement and does not directly contribute to its effective performance. Option D is incorrect because adding an extra encryption layer to Metadata API responses is generally unnecessary and can add undue complexity, as the API should already operate under secure protocols.