Which of the following services utilize radio frequencies?

The correct answer relates to the use of radio frequencies in various forms of communication and detection technologies. Radar and telecommunications are two primary applications that depend on radio waves to transmit and receive signals.

Radar systems utilize radio frequencies to detect and track objects, such as aircraft or ships, by sending out radio waves and analyzing the echoes that bounce back. This is crucial for navigation and safety in aviation and marine operations.

Telecommunications also relies heavily on radio frequencies to enable wireless communication. This includes mobile phones, radio broadcasts, and satellite communication services, all of which depend on the transmission of information over radio wave frequencies. The ability to send and receive signals over great distances and through various mediums is a core aspect of modern communication technologies, making this option the only one directly associated with the utilization of radio frequencies.

In contrast, cooking meals, creating electricity from wind, and filtering air pollutants do not involve radio frequencies. Cooking involves thermal energy, wind energy generation utilizes mechanical power, and air filtration focuses on physical processes to remove pollutants from the air, none of which require radio wave communication.