A pair of branch SRX Series devices are booted up in cluster mode.

The correct answer is C. fxp0 or fxp1 on either device has an existing configuration. The exhibit shows each node reporting itself in hold state and the peer as lost under redundancy group 0. Juniper’s chassis cluster troubleshooting documentation shows this same hold/lost symptom and states that when a node is in hold, it is not ready to operate in a chassis cluster. For branch SRX devices, when cluster mode is enabled, specific physical interfaces are automatically converted into fxp0 for out-of-band management and fxp1 for the HA control link. These interfaces cannot retain normal transit or standalone interface configuration. If the ports that become fxp0 or fxp1 already have configuration, the cluster can enter the hold/lost condition shown in the exhibit.

Option A is wrong because the output does not indicate a Junos version mismatch. Option B is wrong because hardware mismatch is not the symptom being shown. Option D is too specific: a factory-default configuration can cause this problem because it may include configuration on interfaces that become fxp0/fxp1, but the exhibit does not prove specifically that node1 alone is running factory-default configuration. The tested issue is the existing configuration on the interfaces reserved for chassis-cluster management/control. Reference topics: HA Clustering, chassis cluster hold/lost state, fxp0, fxp1, branch SRX cluster initialization.