This past Saturday night I had a FWB over to my place and we fucked, naturally, and the next morning I found a ring on my floor next to my bed.

So today I send her a pic of it asking if it was hers, and she says "No it probably belongs to the other girl you had over".

Now I'm 99% sure it belongs to her because I haven't had any other girls at my place in over a week and I would've found it there already.

Should I respond with something sarcastic, ignore, or just 'okay cool, thanks'?