Which of the following elements indicates the strength of a signal?

The strength of a signal is commonly quantified using decibels (dB). Decibels provide a relative measurement that expresses how powerful a signal is compared to a reference level, which is crucial in fields such as telecommunications and audio engineering. The logarithmic scale of decibels allows for easier comparison of vastly different power levels since it compresses the wide dynamic range of signal strengths into a more manageable format.

While resistance, voltage, and current are important electrical properties, they do not directly measure signal strength. Resistance relates to how much a component impedes the flow of electric current, voltage indicates the potential difference between two points, and current refers to the flow of electric charge. None of these parameters alone adequately indicate the overall strength of a signal, which is why decibel measurement is used as a standard for evaluating signal power.