Form i-709 Line 7 for green card holder

Greetings,

 

I am a green card holder, and Form i-709 applies to me when I send money to my son as a gift. As I am filling the form, I do not understand what I am supposed to write in line 7 (Citizenship). The instructions only talk about two situations (citizen resident and noncitizen nonresident), but neither applies to me (moreover, claiming yourself a citizen when you are not AND claiming yourself a non-resident BOTH disqualify you from ever obtaining citizenship). What am I supposed to write there?

 

Sincerely yours,

Overcurious