Answer:
Radio waves
Step-by-step explanation:
Electromagnetic waves are waves produced by the oscillations of electric and magnetic fields. Electromagnetic waves are the only type of waves that can propagate through a vacuum also, since they do not need a medium to travel through.
Electromagnetic waves are classified based on their frequency, since electromagnetic waves with different frequencies have different properties. From the lowest frequency to the highest frequency, they are:
Radio waves
Microwaves
Infrared waves
Visible light
Ultraviolet
X-rays
Gamma rays
So, the part of the electromagnetic spectrum that has the lowest frequency corresponds to the radio waves. Radio waves have low frequency, between 30 Hz and 30 GHz, and are used for long-distance transmissions, like radio communications, broadcasting, satellites, etc.