In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Ex Input:
Who practices SODIS?, Context: Solar water disinfection (SODIS) involves exposing water-filled plastic polyethylene terephthalate (PET) bottles to sunlight for several hours. Exposure times vary depending on weather and climate from a minimum of six hours to two days during fully overcast conditions. It is recommended by the World Health Organization as a viable method for household water treatment and safe storage. Over two million people in developing countries use this method for their daily drinking water.

Ex Output:
Over two million people


Ex Input:
what field of study is mentioned second to last?, Context: Muslim physicians contributed to the field of medicine, including the subjects of anatomy and physiology: such as in the 15th century Persian work by Mansur ibn Muhammad ibn al-Faqih Ilyas entitled Tashrih al-badan (Anatomy of the body) which contained comprehensive diagrams of the body's structural, nervous and circulatory systems; or in the work of the Egyptian physician Ibn al-Nafis, who proposed the theory of pulmonary circulation. Avicenna's The Canon of Medicine remained an authoritative medical textbook in Europe until the 18th century. Abu al-Qasim al-Zahrawi (also known as Abulcasis) contributed to the discipline of medical surgery with his Kitab al-Tasrif ("Book of Concessions"), a medical encyclopedia which was later translated to Latin and used in European and Muslim medical schools for centuries. Other medical advancements came in the fields of pharmacology and pharmacy.

Ex Output:
pharmacology


Ex Input:
What separates languages in Belgium and the Netherlands?, Context: In the Southern Netherlands (now Belgium and Luxembourg) developments were different. Under Spanish, then Austrian, and then French rule standardisation of Dutch language came to a standstill. The state, law, and increasingly education used French, yet more than half the Belgian population were speaking a Dutch dialect. In the course of the nineteenth century the Flemish movement stood up for the rights of Dutch, mostly called Flemish. But in competing with the French language the variation in dialects was a serious disadvantage. Since standardisation is a lengthy process, Dutch-speaking Belgium associated itself with the standard language that had already developed in the Netherlands over the centuries. Therefore, the situation in Belgium is essentially no different from that in the Netherlands, although there are recognisable differences in pronunciation, comparable to the pronunciation differences between standard British and standard American English. In 1980 the Netherlands and Belgium concluded the Language Union Treaty. This treaty lays down the principle that the two countries must gear their language policy to each other, among other things, for a common system of spelling.

Ex Output:
recognisable differences in pronunciation