What is meant by 'selectivity' in radio receivers?

Selectivity in radio receivers refers to the ability to tune into a specific frequency while effectively ignoring other frequencies. This is a crucial feature because it allows the receiver to focus on the desired signal amidst a multitude of other signals that may be present in the environment. A high selectivity ensures that the receiver can distinguish between closely spaced frequencies, preventing interference from unwanted signals and providing clearer audio quality for the intended transmission.

The nature of radio communication involves receiving signals that can be overwhelmed by noise or competing transmissions. Selectivity enhances the capability of the radio to filter out these distractions. For instance, in crowded frequency bands, the ability to finely adjust the receiver's tuning to a specific frequency ensures that listeners only hear the intended broadcast, without the dilution of other signals.

The other aspects mentioned contribute to the overall functionality of a radio receiver but do not define selectivity. The ability to process multiple signals simultaneously can refer to different methods of managing signals, while sound quality pertains primarily to audio output rather than frequency management. The amplification of all incoming frequencies equally would produce a muddled sound, lacking the discrimination that selectivity provides. Hence, the focus on tuning into a specific frequency underlies the concept of selectivity.