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.

Let me give you an 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.
The answer to this example can be: How many books are there in the British Library?
Here is 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.

OK. solve this:
Article: Renata Di Pietro was studying to be an opera singer. But at 23, while on a music scholarship at the University of Iowa in 1976, her sight began to fail. Soon, it became increasingly difficult to read scores and pick up hand signals from conductors, and the gifted singer was forced to drop out. After moving to Cleveland, Georgia in 2005, Di Pietro relied on guide dogs to get around. Over the years, she became depressed when she'd lose one of the dogs, who had become her best friend, to old age or death. "It's very painful, because you love each one," she says. In 2009, Di Pietro was _ by information from a friend that miniature horses typically live for at least 30 years and make calm and strong guides. She started with a male horse, but he was too hard to control. Angel came next, a mini white female horse Di Pietro has mostly trained herself. "Horses have the ability to avoid the things in the way," she says. "If I am about to run into something, she slides her body in front of me." Di Pietro, now 59, has taught her guide horse to make some sounds with her hoof when she comes to stairs. "Angel can find a chair and locate the nearest door for me," Di Pietro says. Currently, she's training Angel to pull her wheelchair and to fetch. Despite her disability, Di Pietro still sings, performing with her husband, musician Carl Hummer, at special events. Angel is always by her side. "I fight a battle every day to take courage to engage the world," Di Pietro says. "Angel is my warhorse. We fight that battle together."
Answer: She found it difficult to see things clearly.
Answer:
Why did Di Pietro have to give up her studying in the university?