题目

What should you think about in trying to find your career? You are probably better at some school subjects than others. These may show strengths that you can use in your work. A boy who is good at mathematics can use that in an engineering career. A girl who spells well and likes English may be good at office work. So it is important to do well at school. On the other hand, you may not have any specially strong or weak subjects but your records show a general satisfactory standard. Although not all subjects can be used directly in a job, they may have indirect value. Knowledge of histo在30％的蔗糖溶液中，不会发生质壁分离的一组细胞是： （   ）①洋葱根尖生长点细胞   ②人的口腔上皮细胞   ③洋葱表皮细胞④干种子细胞   ⑤蛙卵细胞  ⑥洋葱根毛细胞A．①③④⑤B．①②④⑤C．①③④⑥D．②③④⑤