Explanation: Software-defined transceivers (SDRs) leverage extensive digital processing, allowing manufacturers to integrate sophisticated diagnostic routines directly into the radio's firmware. The built-in self-test feature (C) utilizes these internal capabilities to quickly check various sub-systems, calibrate parameters, and report on the overall health and operational status of the device. It's designed for rapid, internal validation without external equipment. Option (A) describes a thorough, in-depth evaluation suitable for detailed troubleshooting or initial setup, but it is not a *quick overall* assessment. Option (B) provides a rudimentary check only for the transmitter's basic function and doesn't offer a comprehensive evaluation of the entire radio's operational condition (e.g., receiver performance, internal calibration). Option (D) is incorrect; the FCC does not prohibit self-test routines, which are valuable for maintenance and proper operation in both commercial and amateur contexts.