Read the article and select the best answer. Article: Is there a magic cutoff period when children become responsible for their own actions? Is there a wonderful moment when parents can become lookers-on in the lives of their children and shrug , "It's their life," and feel nothing? When I was in my twenties, I stood in a hospital passage waiting for doctors to put a few stitches in my son's head. I asked, "When do you stop worry?" The nurse said, "When they get out of the accident stage. " My mother just smiled gently and said nothing. When I was in my thirties, I sat on a little chair in a classroom and heard how one of my children talked continually and disturbed the class. As if to read my mind, a teacher said. "Don't worry, they all go through this stage and then you can sit back, relax and enjoy them" My mother just smiled gently and said nothing. When I was in my forties, I spent a lifetime waiting for the phone to ring, the cars to come home, the front door to open. A friend said, " They're trying to find themselves, Don't worry, in a few years, you can stop worrying. They'll be adults. " My mother just smiled gently and said nothing. By the time I was 50, I was sick and tired of being weak. I was still worrying over my children, but there was a new wrinkle, there was nothing I could do about it. My mother just smiled gently and said nothing. I continued to suffer from their failures, and be absorbed in their disappointments. My friends said that when my kids got married I could stop worrying and lead my own life. I wanted to believe that, but I was haunted by my mother's warm smile and her occasional "You look pale. Are you all right?" Call me minute you get home. Are you depressed about something ?" Can it be that parents are sentenced to a lifetime of worry? One of my children became quite anxious about me recently, saying, "Where were you ? I've been calling for three days, and no one answered. I was worried. " I smiled a warm smile . The torch has been passed. Question: The author mentioned her ages of twenties, thirties, forties and fifty in order to show _ . Options: A: the hard times she experiences in her life B: the different stages of her children C: the support she received from her mother D: she had been worrying about her children in her life
A:
D