For off-platform use, OmniStudio uses OmniOut so LWC OmniScripts and FlexCards can run on third-party websites. Salesforce documentation explains that an activated OmniScript can be downloaded as an Off-Platform LWC and then added to the OmniOut project for integration into the external application. This makes option B correct because the external site embeds the OmniScript as a Lightning Web Component artifact, not as a Visualforce page. Visualforce is Salesforce-hosted legacy UI technology and is not the primary external embedding model. A REST API could call backend logic, but it would not render the OmniScript user interface. An Integration Procedure call only executes server-side logic; it does not embed the guided OmniScript experience.

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