Socket Mode enables a Slack application to receive Events API payloads and interactive events over a WebSocket connection instead of exposing a publicly accessible HTTP Request URL. Slack's current documentation explicitly states that the WebSocket URL is not static. The application obtains the URL at runtime by invoking apps.connections.open, and Slack refreshes that URL periodically. This architecture is particularly useful for applications operating behind corporate firewalls, during local development, or in environments where exposing an inbound public HTTP endpoint is undesirable. Therefore, B precisely matches Slack's documented description: the application listens through a non-static WebSocket URL dynamically created while the application is running. There is, however, a defect in the supplied question: C is semantically equivalent to B. Slack itself uses the wording “created at runtime,” so C also describes the underlying behavior accurately. Because this is marked as a single-choice question, B should be retained as the intended exam answer, but the alternatives are not sufficiently differentiated to make B uniquely true. This belongs to Tools, particularly Socket Mode, WebSockets, apps.connections.open, and alternative event-delivery architecture.

When a Bolt project is being developed locally through the current Slack CLI, `slack run` can watch application files and automatically restart the local application development server when supported source files change. Slack documents this behavior for Bolt for Python and Bolt for JavaScript projects. Python projects normally watch `.py` files, while JavaScript projects watch `.js` files unless the developer customizes the watch configuration. This live-reload capability shortens the development cycle because developers can modify application logic and have the running process restarted without manually stopping and relaunching it after every edit. The Slack workspace itself is not restarted, the user's browser is unaffected, and OAuth tokens are not regenerated merely because source code changes. Therefore, B is correct.

The Discovery API is specifically designed for Enterprise security, compliance, archiving, and eDiscovery use cases involving extraction of Slack content into approved third-party systems. Slack explicitly describes eDiscovery applications as pulling messages and files from Slack and storing the information in third-party data warehouses, where that content can subsequently be searched, archived, or retrieved. The Discovery API can provide organization-level message and file information, including historical content that remains available under applicable retention and legal-hold policies. Its use is restricted to approved security and compliance scenarios such as eDiscovery, archiving, and Data Loss Prevention. The Audit Logs API provides administrative and security event records rather than the actual body of message and file content needed for an external archive. Admin APIs manage Enterprise configuration and administrative resources. Legal Holds preserve relevant Slack data from deletion or retention-policy expiration but are not themselves the general extraction mechanism described in the scenario. Therefore, D directly matches the legal department's requirement to transfer Slack content into a third-party data warehouse. This question belongs to APIs for Managing Your Slack, specifically Enterprise content governance, eDiscovery, archiving, and Discovery API use cases.