You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Article: There are a lot of public libraries in Britain. These libraries have more than one hundred and fifteen million books, not including those libraries of public schools. Public libraries not only lend books, music records but also help children, patients in hospitals and others to get special play readings, film shows and so on. The first public libraries were founded in about the year 1850. Today's public libraries usually have a reading-room, a lending room and a reference room. The greatest and most famous library in Britain is that of the British Library in London. It was founded in 1973 and has over 10, 000, 000 books. It has nearly every magazine, newspaper and book published in Britain and other parts across the world. 
 Answer: 10,000,000 or less.
Solution: How many books are there in the British Library?
Why? In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

New input: Article: When I was six years old, my mom told me that I could find anyone's number in the phone book. I used to look through the phone book for hours trying to find Michael Jordan's phone number. When I couldn't find it, I just dialed seven numbers. When someone answered, I'd ask, "Is that Michael Jordan?" Obviously, I always had the wrong number. A year later I started playing basketball at my local recreation center. It was very big. I never thought in my wildest dreams that a basketball court could be inside a building. The recreation center had a special smell in it, sort of like hot rubber. I guessed it was from the shoes hitting the floor so fast and hard. The atmosphere on the court was carefree. Our biggest excitement of the day was when we actually made a shot. We celebrated wins over ice cream at a fast food restaurant. I got good at it, and my confidence grew. I played it all the time until the sixth grade. As soon as junior high school came, I stopped playing basketball and focused on school. When senior high school started, I tried out for the school team and made it. We worked hard. Every week we did 300 push-ups and 300 sit-ups on our own. Our coach encouraged the sit-ups to keep stomach power, because it gave us so much control when we were playing basketball. If we didn't want to do the sit-ups and push-ups, we could practice dribbling   and shooting more. It's just us, the ball, the court and the net. But don't take my word for it. See for yourself. After all, I'm just one kid playing the game. 
 Answer: That there was a basketball court inside the building.
Solution:
What surprised the author most at the recreation center?