For modular and scripted inputs in the classic experience, these must run on a separate instance or on-premise ________.

For modular and scripted inputs in the classic experience, these inputs are designed to run on a separate instance or on-premise Intelligent Data Model (IDM). The reason that IDM is the correct answer is that it caters specifically to the processing and collection of data inputs in ways that align with Splunk's methodologies.

IDM can handle custom data inputs which might require additional processing or unique deployment configurations that are not available in the Splunk Cloud infrastructure directly. This separation ensures that the modular or scripted processes can run with the necessary compute resources and configurations without impacting the main Splunk Cloud environment's performance.

The other options, although relevant to storage and computing resources in general, do not represent the specific environment required for running scripted or modular inputs as prescribed by Splunk.