Part 4 Information about the spouse or parent through whom you gained your conditional residence
My hu*****and is an US citizen, he has a A number when he applied his green card several years ago. When I fill in the I-751 form about his information , A-Number (if any) ,which answer I should choose
1.His previous A number
2.None
3.N/A
4.Just leave this answer blank
Thank you in advance for your help.