Hi Elsa. Great question! I want to be as direct and succinct as I can here, without sounding too vague. Don't overthink this. There is often very little time at the end of the interview (perhaps it shouldn't be this way, but it is usually the case) so I would keep it very brief, positive and make the interviewer think a bit too. As much as you are being interviewed, this is your brief window of time to interview the company and be sure it is the best choice for you.
I have always asked, at the end of every interview "What do you not like about working here?" . The interviewer will likely not be expecting this and you will get a very authentic, and unique response. This will speak volumes about the company's culture, as well as the personalities that make up the group.
Additionally, Darlene's comment above is a wonderful question that I would for sure ask:
"How will you know, say six months or a year from now, that you hired the right person?" They usually respond with, "Wow, great question."
I hope this helps!