TN $($Version $7\mathrm{.}00)-$ Building and Securing a Small Network Exam

$8$ Which statement is true about Cisco IOS ping indicators?

$\text{'}$U$\text{'}$ may indicate that a router along the path did not contain a route to the destination address and that the ping was unsuccessful.

$\text{'}$I$\text{'}$ indicates that the ping was unsuccessful and that the device may have issues finding a DNS server.

A combination of $\text{'}.\text{'}$ and $\text{'}$I$\text{'}$ indicates that a router along the path did not have a route to the destination address and responded with an ICMP unreachable message.

:$\text{'}\text{'}$ indicates that the ping was successful but the response time was longer than normal.