If your doctor asked if you perodically masturbated, would you fess up?

I would ask the doctor why he /she wanted to know , then say yes or no.

This did happen to me once in my 20s when I saw a urologist for an exam. He asked how often I masturbated and recommended that I did that "at least twice a week" to maintain my prostate's health. He also took a long time examining my genital and prostate during that exam. I got the feeling that he really enjoyed it.