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: My parents moved to Mississippi when my brother and I were small children, and we were separated from our Oklahoma grandparents by some 600 miles. This long distance allowed us to only visit our grandparents once a year, either at Christmas or during summer vacation. Most of my classmates lived near their grandparents, and I would often hear stories of big families regularly spending time with one another, fishing at "grandpa's" house or going over to "grandma's" for her famous fried chicken. We were disappointed that we did not get to spend more time with our grandparents, but our love for them remained deep and strong. We always expected a road trip to Oklahoma. We would count the days, and when the day came, the entire family would pile into our car at four o'clock in the morning. Crossing the Mississippi River into Louisiana, the scenery changed. Crossing the Red River in Oklahoma, we were in a foreign world. Every trip to see my grandparents can't be without bringing delight. We jumped out of the car in their driveway to be met with bear hugs. My grandparents wanted to know everything about their grandchildren, and we would sit for hours and tell story after story. Grandma had a meal planned, and you could guess she prepared her grandsons' favorite foods. Of course the best part of the visit was that we were able to do whatever we wanted without punishment from our grandparents. Grandma and Grandpa always had presents for us, short trips planned and lovely surprises, such as the time we got to a local restaurant and ate the world's largest hamburger. 
 Answer: Because they lived far away from each other.
Solution:
Why didn't the family visit their grandparents often?