请问8老师，父母移民面试一定要带I864和保税单吗？

请教8老师，我父母在广州面试绿卡移民。他们面试时需要带I864和报税单吗？我看这个网站上说不用啊

https://travel.state.gov/content/travel/en/us-visas/immigrate/the-immigrant-visa-process/step-10-prepare-for-the-interview.html  

“You do not need to bring your Affidavit of Support or financial evidence you submitted to NVC.”

谢谢指教！