Which of the following is NOT a key component of the MPDS protocol?

The correct choice highlights that post-call medical interventions are not a key component of the Medical Priority Dispatch System (MPDS) protocol. The MPDS protocol is designed to provide immediate support and guidance during the emergency call itself, focusing on real-time assessment and instruction to callers regarding their medical situations.

Prioritization of emergency calls, provision of pre-arrival instructions, and assessment of emergency situations are central to the protocol, as they ensure that the most urgent cases are prioritized for response, that effective instructions are given while help is en route, and that dispatchers accurately assess the situation to ensure appropriateness of the response. Post-call medical interventions fall outside the purview of the EMD's role, as they pertain to actions taken after the call has concluded, which the dispatcher does not manage.