To answer this question, you need to understand the concept of the default ID for SCSI HBA (Host Bus Adapter).
The default ID for SCSI HBA is commonly set to 7. SCSI devices are connected to the SCSI bus, and each device on the bus is assigned a unique ID. The SCSI HBA is also a SCSI device, and it typically has an ID assigned to it as well.
The ID determines the priority of the device on the bus, with the lowest ID having the highest priority. The default ID for the SCSI HBA is often set to 7 because it is the highest possible ID value. This allows other SCSI devices with lower IDs to be given higher priority.
Therefore, the correct answer is:
C. 7