Epson R2880

When I go to open a photo in Adobe Photoshop CS3 I keep getting the following. What should I do?
Thank you

The document does not have an embedded RGB profile

What would you like to do?

1) Leave as is (don’t colour manage)

2) Assign working RGB Adobe RGB 1998

3) Assign profile Adobe RGB 1998 (in the drop down box there is a number of options including SPR 2880 with different type of papers)

& then convert document to working RGB