阅读下面短文，从短文后面各题所给的四个选项(A、 B、C 和 D)中选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。

    Jim and his brother lived on the 80th level. When coming home one day, to their 1, the lifts were not working and they had to 2the stairs.

    After reaching the 20th level, breathless and tired, they decided to3their bags and come back for them the next day. They climbed4. When they got to the 40th level, Jim's brother started to 5. However, they6to climb the flights of steps, arguing all the way to the 60th floor.

    They then 7that they only had 20 levels more to climb and decided to stop arguing and continue climbing8. They reached their home at long last. Each stood calmly before the door and waited for the other to9the door. And they realized that the10 were in their bags which were left on the 20th floor.

    This story is a reflection (反映) of our life. When 11, many of us are asked to do as our parents and teachers expect. We 12 get to do the things that we really like and love and are under too much pressure (压力) 13 by the age of 20, we get tired and decide to14 this load (负担).

    Once 15  of/ about the pressure, we work harder to realize our dreams. But by the time we reach 40 years old, we find it 16 to realize them and begin to feel unsatisfied and complain, and 17them. Reaching 60, we realize that we have18 cause for complaint anymore, and we begin to walk the final stage with19.

    So follow your dreams and20for them carefully, never complain and lose your key, and your dreams will come true one day.