Which of the following statements is correct for the use of packet switching?

• A. the subdivision of information into individually addressed packets in conjunction with alternative routing arrangement enabled the transmission path to be altered in the event of congestion or individual link failure
• B. the employment of additional intelligence within the network enabled more sophisticated error control and link control procedures to be applied
• C. by employing wide bandwidth circuits for the trunk networks substantial economies through extensive sharing of capacity could be achieved.
• D. All of the above