An update for those of you who are not US citizens and submitting their application:
Even if you ARE a permanent resident (i.e., not a nonimmigrant alien), you MUST provide your alien number in 10.B and a copy of your permanent resident card (green card).
This is very confusing since section 10 is titled "Nonimmigrant Alien Certification of Compliance."
I just got a letter from the DOJ asking me to provide that number as well as a copy of my green card.
I wish they had made that clear.