Which component amplifies the signals in a radio system?

The component that amplifies the signals in a radio system is the amplifier. In radio communications, the primary role of an amplifier is to increase the strength of weak signals to levels that can be effectively transmitted or processed. This is crucial because radio signals often need to travel long distances, and without amplification, the signals would succumb to noise and attenuation, rendering them ineffective.

An amplifier boosts the radio frequency signal to ensure it can overcome any potential losses and be clearly received at the other end of the transmission line. It plays a vital role in both transmitting and receiving units, enhancing the clarity and distance of communication.

While transmitters and receivers are important components of a radio system, their primary functions are to send and receive signals, respectively. A modulator, on the other hand, is responsible for encoding information within the carrier signal but does not amplify it. The amplifier's role specifically focuses on increasing signal strength, which is why it is the correct answer in this context.