根据短文内容，从A、B、C、D四个选项中选出一个能填入相应空格内的最佳答案。
Tom worked hard in an office. But it seemed that there was little change in his life. He was unhappy and didn't want to improve himself any more. His father, Joe, knew this and decided to have a talk with 1 .
One day, Tom and his father went for a walk after dinner. 2 they were walking along a river, Tom said, “Dad, you always tell me to learn something new. To be3, I don't want to make any change.”
Joe looked in the river, saw a dead 4and pointed at it.
“Tom, what is that over there?”
“It's a dead fish.”
“What's the fish doing?”
“It's moving down with the running water.”
“But the fish is dead. 5 can it be moving?” asked Joe.
“It's moving as the river is moving.”
Joe turned to his son and said, “Life is 6 the river. It's always moving and always changing. Some people don't want to change, but their life is always changing whether they like it or not. A dead fish only moves along the river, while a living fish can control its journey. What's your choice if you want to live a 7 life?”
This made Tom 8 his aunt who had already stopped learning and developing. And she just stayed the way she used to be, living like a dead fish.
Guided by his 9 , Tom understood what he said. He didn't want to become a person like his aunt. So he made up his mind to 10 learning and developing himself.
