Which of the following is not a function of the data link layer?
a. deciding when to transmit messages over the media
b. formatting the message by indicating where messages start and end, and which part is the address
c. detecting and correcting any errors that have occurred in the transmission of the message
d. specifying the type of connection, and the electrical signals, radio waves, or light pulses that pass through it
e. controlling the physical layer by determining when to transmit
Answer: d