203.
M: Did you ever win anything?
W: Well, yes, I did. I came in first in this little competition in the local newspaper, and it was this competition where you had to, um, finish the sentence "School is..."
M: Right.
W: And design a poster and because I was quite a good student at the time, I said "School is the key to a new and better world."
M: So how old were you then?
W: It was ten years ago, and I was eleven.
M: Oh, right. So what did you win then?
W: I won a 20-dollar gift certificate to Hathaway House Bookshop, and I spent the whole summer there because twenty dollars were quite a lot then. I still have the books that I bought there.
M: Lucky you.
答案解析：
(1) 正确答案为B。根据design a poster 设计海报，可知，女子参加的是一个设计比赛。因此B项正确。
(2) 正确答案为A。根据It was ten years ago, and I was eleven. 那是十年前的事了，当时我11岁。可知A项正确。
(3) 正确答案为C。根据I won a 20-dollar gift certificate. 我赢得了一张价值20美元的礼券。可知，女子的奖品是礼券，因此C项正确。本题易错选为A，对话中20美元是礼券的价值，而不是女子赢得的奖金，因此A项排除。