Which of the following statements are true about the Internet? I. The routers in the Internet are Ethernet routers because they look at the information associated with the Ethernet protocol in making the decision to forward the packets to the destination computer. II. The main purpose of the IP protocol is to ensure that network packets are reliably transmitted on a communications link. III. The main purpose of the TCP protocol is to segment the file at the source computer and reassemble the packets to recover the file at the destination computer. IV. The Ethernet protocol being a link-level protocol would ensure the reliable transfer of packets over the Ethernet LAN.