What is the most common implementation of PAT in a standard networked environment?

What is the most common implementation of PAT in a standard networked environment?
A. configuring multiple internal hosts to communicate outside of the network using the outside interface IP address
B. configuring multiple internal hosts to communicate outside of the network by using the inside interface IP address
C. configuring multiple external hosts to join the self-zone and to communicate with one another
D. configuring an any any rule to enable external hosts to communicate inside the network