packet switching

I encountere开发者_如何学运维d this question in one of the exams that ,

Which of the following is based on the packet switching network?

(A) LAN (B) WAN (C) MAN (D) VPN

To me, it seems that all of them are packet switched. What should be the correct answer?

From wikipedia -

The most well-known use of packet switching is the Internet (which is basically a type of 
WAN) and local area networks (or, LAN).

My bet will be on LAN ( if I have to choose only one of the options ;-) )