Question

which is the definition of telegraphy? (1 point)
○ the science of creating sound waves using pulses in a symbolic code
○ the science of using or making communication systems to transmit or reproduce information
○ the transmission of signals using light waves from things such as lighthouses
● the transmission of radio waves that get converted back into sound waves at the receiver

Explanation:

Telegraphy involves transmitting information using electrical signals (in the case of radio - telegraphy, radio waves are used). The key concept is the transmission of signals (here radio waves) which are then converted back into a usable form (sound waves at the receiver in some telegraph - related systems, especially when considering audio - telegraphy aspects).

Answer:

the transmission of radio waves that get converted back into sound waves at the receiver