I feel almost anything would be good, at first - just to show I had human like sentience..
One small example would be "Don't kill me. I have something to tell you"
Or if I had plenty of time
"Hello, I am the ant you can see. I was once human. To prove it, ask me a question and wait while I write the answer..."
Something like that
Once I'd been proven an "ex human" I'd probably demand to see my lord and saviour, Sir David Attenborough
Ask a more specific question? I've played all of them...