Question: To permanently add NAT to the default zone using firewalld, you would use which command string?

1. `firewall-cmd --permanent --add-nat`
2. `firewall-cmd --permanent --add-masquerade`
3. `firewall-cmd --zone=default --add-nat`
4. `firewall-cmd --zone=default --add-masquerade`

Answer: The correct answer of the above question is Option B:`firewall-cmd --permanent --add-masquerade`