This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[EX Q]: Passage: The Tibetan Empire emerged in the 7th century, but with the fall of the empire the region soon divided into a variety of territories. The bulk of western and central Tibet (Ü-Tsang) was often at least nominally unified under a series of Tibetan governments in Lhasa, Shigatse, or nearby locations; these governments were at various times under Mongol and Chinese overlordship. The eastern regions of Kham and Amdo often maintained a more decentralized indigenous political structure, being divided among a number of small principalities and tribal groups, while also often falling more directly under Chinese rule after the Battle of Chamdo; most of this area was eventually incorporated into the Chinese provinces of Sichuan and Qinghai. The current borders of Tibet were generally established in the 18th century. Question: Which Chinese provinces used to be the eastern part of Tibet?
[EX A]: Sichuan and Qinghai

[EX Q]: Passage: The Yuan dynasty is considered both a successor to the Mongol Empire and an imperial Chinese dynasty. It was the khanate ruled by the successors of Möngke Khan after the division of the Mongol Empire. In official Chinese histories, the Yuan dynasty bore the Mandate of Heaven, following the Song dynasty and preceding the Ming dynasty. The dynasty was established by Kublai Khan, yet he placed his grandfather Genghis Khan on the imperial records as the official founder of the dynasty as Taizu.[b] In the Proclamation of the Dynastic Name (《建國號詔》), Kublai announced the name of the new dynasty as Great Yuan and claimed the succession of former Chinese dynasties from the Three Sovereigns and Five Emperors to the Tang dynasty. Question: Who was Kublai Khan's grandfather?
[EX A]: Genghis Khan

[EX Q]: Passage: Stansted Airport, north east of London in Essex, is a local UK hub and Luton Airport to the north of London in Bedfordshire, caters mostly for cheap short-haul flights. London City Airport, the smallest and most central airport, in Newham, East London, is focused on business travellers, with a mixture of full service short-haul scheduled flights and considerable business jet traffic. London Southend Airport, east of London in Essex, is a smaller, regional airport that mainly caters for cheap short-haul flights. Question: What is the smallest airport in the London area?
[EX A]:
London City Airport