[setzf]

if you raise the flop then co would be getting 8.5-1 which would protect you from a gutshot. as it stands by just calling co is getting 16-1 which would make just calling with just a lone A sometimes correct. there's no flush draw and you cant protect from middle or bottom pair but you can protect from a gutshot and overcard by raising so i think you have to do it. if in fact your opponnent had 78 then calling the flop instead of raising has turned out to be a terrible mistake. besides that i would just call down the river.