Explanation: A superregenerative receiver (A) is a type of regenerative receiver where the detector is intentionally operated in a mode that causes it to periodically break into and out of oscillation. This rapid cycling, known as quenching, occurs at a rate above the range of human hearing (supersonic). This characteristic provides immense gain with a very simple circuit and effectively demodulates amplitude-modulated (AM) and wideband frequency-modulated (FM) signals. The question's description precisely matches the defining principle of a superregenerative receiver. Superheterodyne receivers (B) operate by converting the incoming radio frequency to a fixed intermediate frequency (IF) using a mixer and local oscillator; they do not rely on a detector cyclically entering and leaving oscillation. A discriminator (C) is a circuit within an FM receiver that converts frequency variations into amplitude variations, serving as a demodulator, not a type of receiver architecture with this oscillating characteristic. "Detuned radio frequency receiver" (D) is not a standard receiver classification.