Given the task definition, example input & output, solve the new input case.
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.
Example: 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.
Output: How many books are there in the British Library?
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 case for you: Article: Everyone needs safe drinking water, but about 1.1 billion people have no access to clean water. Most of the world's water is salty ocean water or frozen polar ice. By 2050, the world's population could grow from 6.7 billion to more than 9 billion. All of those people will need water to drink. But the bad news is that some areas of the world are growing drier because of climate change. The total area of the Earth's surface classified as very dry has doubled since the 1970s. Sadly, the precious resource is still misused in industry, in farming and at homes. Therefore, the world is facing a crisis over water. "You do the math, and it gets a little scary," says Stuart Minchin, a water expert in Australia. "We're waking up," he says. "But not fast enough." In southern Australia, farmers have been hit hard. They can't irrigate their fields well enough. The Australian government has launched a $1.3 billion project to improve Australia's irrigation system to stop the crop production dropping further. Australians have serious water worries, but it could be worse. They don't have to fear that when they turn on the tap, nothing will come out. That's the case in India. Many people in New Delhi, the capital, go without clean water for days. City leaders have taken stricter measures to save water. Users pay a very high but affordable price for it. Homeowners who waste water are given large fines. There are 1.9 million people who live in Las Vegas, Nevada. Now it has grown by more than 300,000 people since 2002. But it uses less water today than it did seven years ago.
Answer: Water's becoming salty.
Output:
Which of the following is NOT a reason for a water crisis?