Explanation: A regenerative receiver operates by employing a unique positive feedback mechanism to achieve high sensitivity and gain with minimal components. First, an incoming RF carrier is indeed coupled into the receiver's tuned-grid circuit and applied to the grid of the active device (A). This initial step selects the desired frequency. The signal is then amplified in the usual manner (B, first part). The key to regeneration is that a controllable portion of this amplified plate (or collector/drain) signal is coupled back into the grid circuit (B, second part). This feedback signal is critically in phase with the original incoming signal (C). This positive feedback causes the signal to be re-amplified, reinforcing itself multiple times and dramatically increasing the effective gain and sensitivity of the receiver. Because all three statements (A, B, and C) accurately describe integral parts of a regenerative receiver's operation, "All of the above" is the correct answer.