Explanation: Detection, also known as demodulation, is the crucial process within a radio receiver that recovers the original information, or "intelligence," from the modulated radio frequency (RF) carrier wave. When a signal is transmitted, the information (like voice or data) is encoded onto a high-frequency carrier through modulation. The detector circuit at the receiver essentially "undoes" this modulation, extracting the original intelligence that was impressed on the carrier. * **A) Masking out the intelligence** is incorrect. An S-meter measures signal strength, and the detection process is about *recovering* intelligence, not hiding it. * **C) The modulation of a carrier** is the opposite process, performed by the transmitter to impress intelligence onto the carrier. * **D) The mixing of noise** is an unwanted phenomenon that degrades reception, not the definition of how information is recovered.