Which of the following is a main use of a very high frequency (VHF) radio?

The main use of a very high frequency (VHF) radio is for distress calling and safety. VHF radios are specifically designed for marine communication, allowing boaters to send and receive important safety information, communicate with other vessels, and contact rescue services in the event of an emergency. This feature is vital for ensuring the safety of individuals on the water, as it provides a means to quickly alert others about distress situations.

While some might think that VHF radios can be used for other purposes, such as playing music or merely watching other vessels, that's not their function. Additionally, although VHF radios can transmit weather information, they are not exclusively dedicated to that purpose, making the broad capability of distress calling and overall safety their primary function. This highlights the crucial role of VHF radios in marine environments, serving not only as a communication tool but as an essential safety device for boaters.