Teacher: 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.
Teacher: Now, understand the problem? If you are still confused, see the following 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.
Solution: How many books are there in the British Library?
Reason: In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

Now, solve this instance: Article: A South African farmer is receiving phone calls from his sheep after equipping them with cell phones to keep tabs on the flock amid recent livestock thefts, according to local press Wednesday. When the sheep call, it is always bad news for farmer Erard Louw of the Cape Town suburbs, as the phones around their necks are only set to switch on when the sheep start running, a sign that thieves have cut through the fences. "As they run it gives me a phone call and says 'Sheep One' or 'Sheep Two' and so on, so at least I know where to start looking because the farm is 750 hectares (1,850 acres)," Louw told the Cape Times daily. Louw attached the phone-like security device to the collars of four sheep in separate flocks after thieves sneaked in and stole 27 sheep and 13 lambs a couple of weeks ago, driving Louw to _ for ways to protect his animals. He said there was no use calling nearby police, as they were stationed too far away and in his experience they either lacked an available car or the vehicle was out of fuel or missing tyres -- also the work of thieves. According to Louw, the cell phones have already proved their worth, with one sheep-snatcher caught thanks to the device. Still, with theft attempts currently at their peak, given long winter nights and early nightfall, a few sheep-robbers managed to get away in spite of the device. "The phone did start ringing that night and I went out," he said, but added that he was too late.
Answer: Because he wanted to protect them against thieves.
Student:
Why did Erard Louw attach the phone-like device to the sheep he raises?