When I was in the third grade, I was picked to be the princess in the school play. For weeks my mother had helped me practice my lines. But once on stage, every word disappeared from my head. Then my teacher told me she had written a narrator's part for the play, and asked me to change roles. Though I didn't tell my mother what had happened that day, she sensed my unhappiness and asked if I wanted to take a walk in the yard. It was a lovely spring day. We could see dandelions(蒲公英）popping through the grass in bunches, as if a painter had touched our landscape with bits of gold. I watched my mother carelessly bend down by one of the bunches. "I think I am going to dig up all these weeds," she said. "From now on, we'll have only roses in this garden." "But I like dandelions," I protested. "All flowers are beautiful-even dandelions!" My mother looked at me seriously. "Yes, every flower gives pleasure in its own way, doesn't it?" she asked thoughtfully. I nodded. "And that is true of people, too," she added. When I realized that she had guessed my pain, I started to cry and told her the fact. “But you will be a beautiful narrator,” she said, reminding me of how much I loved to read stories aloud to her. Over the next few weeks, with her continuous encouragement, I learned to take pride in the role. The big day finally came. A few minutes before the play, my teacher came over to me. “Your mother asked me to give this to you,” she said, handing me a dandelion. After the play, I took home the flower, laughing that I was perhaps the only person who would keep such a weed.
The girl did not play the role of the princess mainly because_____  

A．she felt nervous on the stage.

B．she lost her interest in that role.

C．she preferred the role of the narrator

D．she had difficulty memorizing her words

Why did the mother suggest a walk in the garden?

A．To remove the dandelions

B．To enjoy the garden scene

C．to help her daughter with the play.

D．to have a talk with her daughter.

What is the main idea of the story?

A．Everybody can find his or her own way to success.

B．Everybody should learn to play different roles

C．Everybody has his or her own value in the world.

D．Everybody has some unforgettable memory.