Explanation: Mixers combine the incoming radio frequency (RF) signal with a local oscillator (LO) signal to produce an intermediate frequency (IF). They are designed to operate non-linearly to create these new frequencies. However, when excessive signal energy overdrives the mixer, its non-linearity becomes extreme. This results in the generation of numerous unwanted frequencies, known as **spurious mixer products** or intermodulation distortion. These products can appear as "ghost" signals or interference, significantly degrading the receiver's performance by masking weak desired signals or creating false ones. Automatic limiting (A) is a function typically found in IF stages or dedicated limiter circuits, not the direct result of mixer overdrive. Mixer blanking (B) is a technique used to suppress pulse noise. Instability and drifting (D) are usually associated with oscillator design or component issues, not the primary and immediate consequence of an overdriven mixer's non-linear behavior.