I didn't provide proof of residency in my application, I just stated that I've lived in Oregon all of my life. I later received an email from the administrative manager asking for proof of residency, which can include: 1) being legally dependent upon a parent who is an Oregon resident (2019 tax forms could prove that), 2) Oregon driver’s license, 3) voter registration card, 4) personal 2019 federal taxes indicating Oregon residence and presence in Oregon, 5) current automobile registration, 6) rental or lease agreement, etc.
Hope that helps!