NAT Inside command CCNA practice question

Question:

I was taking Catalyst 3560V2 a practice CCNA exam and had a question on NAT. I was just curious if anyone could help clarify if this is the correct answer and why?

The question was on how many interfaces of R1 need the "ip nat inside" command to grant external internet access to the entire network. I've attached a screen shot but, the topology was R1 with 4 ports. FA0/1 - 3 and a s0/0/0 port. the s0/0/0 port was going out to the ISP. The other three ports each had a switch and some pc's connected...

My answer was the command would need to go on the 3 Fast Ethernet ports... but the answer was all 4 ports.


Answer:

if your next hop of ser0/0 is to an isp (public addtessing) then yes i would agree with you.

unfortunately i am not able to see your topology Catalyst 3560X Price to check .