Match the following:
| i. PSTN | a. Virtual Switching |
| ii. X.25 | b. Packet switching |
| iii. Internet | c. Circuit Switching |
| iv. Frame Relay | d. Datagram Switching |
Match for i , ii , iii, iv respectively is:
1
a , b , c , d
2
c , a , d , b
3
c , d , a , b
4
b , c , d , a