Which statement best describes the process of how NAT $($Network Address Translation$)$ works?

Which statement best describes the process of how NAT $($Network Address Translation$)$ works?

what is the answer?

$1.$NAT translates DNS addresses from public to private for efficient name resolution.

$2.$NAT translates IP addresses from private to public for internet connectivity.

$3.$NAT translates IP addresses from public to private for secure communication.

$4.$NAT translates MAC addresses from private to public for network routing.