Changes in behaviour can indicate "interference", but from what you gave written it just sounds like a normal little girl starting to realise that boys and girls are different. There would be other behaviour changes as well if there was something more to worry about. Maybe this link will help reassure you....
Family Planning Queensland :: Traffic Lights guide to sexual behaviours in children and young people: identify, understand and respond


Kid's will be all different ages and sometimes they learn from things we were not expecting, so maybe she's seen someone react in a particular way on TV or other family or friends. It seems more likely that she has learned its a way of controlling things as she gets 1:1 attention if she is taken into another room, so maybe it's just that. Just monitor and keep reinforcing that nudity isn't a big deal.