Comprehensive and Detailed Explanation:
The correct answers are A and C.
* A - If responses are not received within the configured Conversation Window (e.g., 30 mins, 1 hour), MobileConnect treats them as unrelated and sends the default response.
* C - If a Next Keyword is not specified on the outbound message, MobileConnect has no instruction for how to handle a reply, so it falls back to the default keyword response.
# Why others are wrong:
* B: The Conversation Window is based on minutes/hours, not 24 hours.
* D: If a response contains "stop," it triggers an opt-out process, not a fallback default keyword response.
Exact Extract from Salesforce Official Documentation:
Salesforce Help - MobileConnect Conversation Window and Next Keyword Setup:
"Ensure that outbound messages include a configured Next Keyword to direct subscriber responses.
Responses received outside the Conversation Window are treated as unrelated and routed to the default keyword response." (Source: https://help.salesforce.com/s/articleView?id=sf.mc_ms_conversation_window.htm)
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