Which statement describes correctly what happens when a packet moves through a router?

A. The destination IP address is changed to the original destination.
B. The packet’s TTL is decremented.
C. The source MAC address is changed to the original source MAC address.
D. All of the above

B. The TTL, or time to live, is decremented usually by one. When the TTL reaches zero, a packet is considered un-routable. This prevents packets from eternally routing.