The correct answer is A because Remote Engagement video traffic requires Twilio endpoints to be trusted by the Salesforce org. Salesforce Help for setting up Twilio for Remote Engagement states that participants can connect to video calls by adding Twilio WSS endpoints as Trusted URLs in the Salesforce org. This is specifically required for secure video-call connectivity, which directly matches the symptom in the question: the Twilio credentials and Experience Cloud site are configured, but the video media fails to load.

Twilio External Credentials handle authentication and connection details for the integration, and the Experience Cloud site provides the HCP-facing remote engagement experience. However, browser and Salesforce security controls still need to allow the required Twilio WebSocket Secure traffic. If those URLs are not trusted, the page can load while the actual audio/video media connection fails.

Option B is incorrect because assigning a field-sales permission set to the Site Guest User would be inappropriate and overly permissive. The issue is media connectivity, not guest-user access to sales functions. Option C is also incorrect because a trigger handler for remote-session invitations would relate to record automation or invitation behavior, not secure loading of Twilio video traffic. Therefore, the consultant must add Twilio’s required endpoints to Trusted URLs .

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