This happened to my girlfriend (now wife) when we just started dating. She was VERY shy when we started dating so she had to be clueless (Choice A from post 1) about the show she was putting on.
I went to her apartment to pick her up to go out and when I pulled up and parked a male neighbor of hers was standing in the parking lot looking up towards her slider, her apartment was on the 2nd floor. I didn't really think anything of it since I assumed he was standing out there waiting for someone or had been smoking. I got out of the car and said hi to him and started walking towards the apartment door. As I did I took a look up at her slider which had the blinds open to her living room and I noticed I could see at an angle into her bathroom. I could see that the bathroom light was on and I could see her sink, her mirror and all the way back to her bathtub though I didn't see her. It was getting dark outside so the view into her apartment was great.
When I got in the apartment my girlfriend only had her bra and panties on and was in the bathroom doing her hair and would have been in full view of anyone outside. I wanted to know if she was seen nude (hoping she was
) so I asked her why she left the bathroom door open and she said it gets too hot when she is in there when the door is closed. Remember she was shy at this point in our relationship so I had to proceed slowly. I found out later she had taken a bath which included her getting up on her knees and taking care of her trim. If the neighbor was there a couple of minutes before I arrived he probably saw everything she has, either when she was in the bathtub or when she got out to dry off. I was very happy to know that she was seen nude!
As I get time I will post more on how I turned my very shy girlfriend into a willing exhibitionist.