Detailed Instructions: 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.
See one example below:
Problem: 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?
Explanation: In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

Problem: Article: Treat with Respect The speed with which Man is changing the face of Earth has outstripped all the mighty processes of nature put together. In his haste to supply himself with increasing quantities of Earth's treasures he risks destroying one he greatly needs, his natural surroundings. Some countries set aside unspoiled areas of natural beauty. prefix = st1 /Canadahas the largest system of national parks in the world, 29 in all covering about 13 million hectares, preserving the different landscapes and the plant and animal life. Other countries are restoring areas which have been reduced to waste land by mining. At Broken Hill in Australiadrifting sand from rock crushing turned the area into a desert swept by sand storms. This is now being irrigated, fertilized and planted with grass and trees. In Great Britain quarries and gravel pits  are being filled in or made into lakes, industrial wasteland is being turned into playing fields and waste tips into sloping green hills. However Man tries to look after Earth, the fact is that he is using up at a great rate resources, especially fuel resources, which have taken millions of years to accumulate and which he cannot renew. Yet every day the Earth receives a huge supply of energy from the Sun. Man has made several experiments in using solar energy to heat furnaces , cookers, and water-distillers. In space technology, e.g. on satellites, solar cells convert  sunlight into electricity. Houses and offices have been designed which are centrally heated by water or air heated by the sunlight. When Man can trap and store this energy, so that he can use it exactly as he needs it, he will have not only an endless supply, but a clean and safe one. 
 Answer: Energy from the Sun.
Solution:
According to this selected passage, which energy is considered to be endless, clean and safe?