阅读短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。
Wang
Bing is a 12-year-old boy. He and his parents live together. He likes sports
very much and does well in sports.
One
afternoon, he comes out of the classroom and sees his father waiting for him at
the school gate. He is very glad and runs to his father.
"Dad,
please don't wait for me next time. I can go home by myself. I have grown up,"
says Wang Bing.
"Let's
go," says his father, "I'll cook supper and you can do your homework
at home. Mum is still at work."
On
their way home, Wang Bing sees some boys skating in a park. "Can I go to
learn skating, Dad?" asks Wang Bing. "I'm sorry, my boy. You must go
home and do your homework," answers his father, "but I can buy you an
ice cream."
Then
his father buys an ice cream for him. When Wang Bing wants to eat it, a fly (苍蝇) flies to the ice cream.
"Drive
off the fly." says his father. "It's very dirty (脏的)." But Wang Bing
says with a smile, "You don't let me skate, but can you let it skate for a
while (一会儿)?"
