What distinction does the author draw between packet switching and circuit switching?

A
Circuit switching and packet switching are different ways in which information can be accessed on multiple computers at once.
B
Packet switching allows a wireless connection while circuit switching requires a physical connection.
C
Packet switching allows information to be accessed on multiple computers, while circuit switching can only share data between two computers.
D
Circuit switching allows information to be accessed on various computers at the same time, while packet switching is the communication between two computers.