例：—How many pencils do you need?
—I need four pencils. 
—How much are they? two dollars for one
—They are eight dollars.
—I need . 
50 dollars for one
—How much ?
— . fifty dollars for one
—I need . 
—How much ?
— . three dollars for one
Wang Bin is a football fan. There is a football match between a Chinese team and an English team. He wants to watch it. He comes to the box office(售票处) and gives the clerk 10 yuan. The clerk says, "Please give me another 10 yuan. The price(价格) of a ticket is 20 yuan."
"Why?" says Wang Bin, "I just want to watch the Chinese team. I don't want to watch the other team at all. Do you want me to buy a ticket for them?"
B. 
C. 
D. 
E. 
