单项选择题

TEXT D
When you are small, all ambitions fall into one grand category: when I’ m grown up. When I’ m grown up, you say, I’ll go up in space. I’ m going to be an author. I’ll kill them all and then they’ll be sorry. I’ll be married in a cathedral with sixteen bridesmaids in pink lace. I’ll have a puppy of my own and no one will be able to take him away. None of it ever happens, of course-- or darn little, but the fantasies give you the idea that there is something to grow up for. Indeed, one of the saddest things about gilded adolescence is the feeling that from eighteen on, it’ s all downhill; I read with horror of an American hippie wedding where someone said to the groom (aged twenty) "you seem so kinda grown up somehow", and the lad had to go round seeking assurance that he wash’ t. No, really he wasn’t. A determination to be better adults than the present incumbents are fine, but to refuse to grow up at all is just plain unrealism.
Right, so then you get some of what you want, or something like it, or something that will do all right; and for years you are too busy to do more than live in the present and put one foot in front of the other, your goals stretching little beyond the day when the boss has a stroke or the moment when the children can bring you tea in bed—and the later moment when they actually bring you hot tea, not mostly slopped in the saucer. However, I have now discovered an even sweeter category of ambition. When my children are grown up, I’ll learn to fly an airplane. I will career round the sky, knowing that if I do "go pop", there will be no little ones to suffer shock and maladjustment; that even if the worst does come to the worst, I will at least dodge the geriatric ward and all that look for your glasses in order to see where you’ ye left your teeth. When my children are grown up, I’ll have fragile lovely things on low tables; I’ll have a white carpet; I’ll go to the pictures in the afternoons. When the children are grown up, I’ll actually be able to do a day, s work in a day, instead of spread over three, and go away for a weekend without planning as if for a trip to the Moon. When I’ m grown up—I mean when they’ re grown up—I’ll be free.
Of course, I know it’s got to get worse before it gets better. Twelve-year-old, I’ m told, don’t go to bed at seven, so you don’t even get your evenings. Once they’ re past ten you have to start worrying about their friends instead of simply shooing the intruders off the doorstep, and to settle down to a steady ten years of criticism of everything you’ ve ever thought or done or worn. Boys, it seems, may be less of a trial than girls, since they Can’t get pregnant and they don’t borrow your clothes—if they do borrow your clothes, of course, you’ve got even more to worry about.
The young don’t respect their parents any more, that’s what. Goodness, how sad. Still, like eating snails, it might be all right once you’ ye got over the idea; it might let us off having to bother quite so much with them when the time comes. But one is simply not going to be able to drone away one’s days, toothless by the fire, brooding on the past.
Young people often feel that the age of eighteen is the______.