The effectiveness of VHF communications is maximized by:

The adjustment of squelch for maximum receiver sensitivity, setting transmitter power to 1W & selecting an appropriate channel.

Appropriate setting of the transmitter power, selecting an appropriate channel & adjustment of squelch for maximum receiver sensitivity.

Selecting an appropriate channel, adjustment of squelch for minimum receiver sensitivity & setting transmitter power to 1W.

Selecting an appropriate channel, adjustment of squelch for minimum receiver sensitivity, setting transmitter power to 25W.

The effectiveness of VHF communications is...