IP addresses allow datagrams to move from source to destination. Which of the following is a valid public IP address?

$192\mathrm{.}168\mathrm{.}21\mathrm{.}124$

$172\mathrm{.}16\mathrm{.}1\mathrm{.}1$

$171\mathrm{.}16\mathrm{.}4\mathrm{.}3$

All of the above