Which of the following matches JREAP B to its correct encryption devices?

The correct match for JREAP B and its encryption devices is the combination of external or embedded KG-84As or KIV-7s. JREAP (Joint Range Extension Applications Protocol) B is a communication protocol designed to extend the range of tactical data links, which require robust encryption for secure transmission. The KG-84A and KIV-7 are both encryption devices widely used within military communications.

The KG-84A is a secure voice and data encryption device that's adaptable for various communications environments, while the KIV-7 provides secure military communications that are essential for maintaining confidentiality over tactical networks. The appropriate pairing of these encryption devices with JREAP B ensures compliance with military security standards, thereby safeguarding the transmission of critical operational data.

The other options, while they may mention secure protocols or networks, do not specifically relate to the direct encryption methods that align with JREAP B. Therefore, the option highlighting the use of external or embedded KG-84As or KIV-7s is the most accurate in this context.