input question: Extract the answer to the question from the following context. Question: what time period was mentioned last? Context: General Dong Zhuo (d. 192 AD) found the young emperor and his brother wandering in the countryside. He escorted them safely back to the capital and was made Minister of Works, taking control of Luoyang and forcing Yuan Shao to flee. After Dong Zhuo demoted Emperor Shao and promoted his brother Liu Xie as Emperor Xian, Yuan Shao led a coalition of former officials and officers against Dong, who burned Luoyang to the ground and resettled the court at Chang'an in May 191 AD. Dong Zhuo later poisoned Emperor Shao.???
output answer: May 191 AD

input question: Extract the answer to the question from the following context. Question: Which nickname is its official nickname? Context: Montana i/mntn/ is a state in the Western region of the United States. The state's name is derived from the Spanish word montana (mountain). Montana has several nicknames, although none official, including "Big Sky Country" and "The Treasure State", and slogans that include "Land of the Shining Mountains" and more recently "The Last Best Place". Montana is ranked 4th in size, but 44th in population and 48th in population density of the 50 United States. The western third of Montana contains numerous mountain ranges. Smaller island ranges are found throughout the state. In total, 77 named ranges are part of the Rocky Mountains.???
output answer: none official

input question: Extract the answer to the question from the following context. Question: The absence of flooding and what else has helped the US have a climate useful for farming? Context: Due to its large size and wide range of geographic features, the United States contains examples of nearly every global climate. The climate is temperate in most areas, subtropical in the Southern United States, tropical in Hawaii and southern Florida, polar in Alaska, semiarid in the Great Plains west of the 100th meridian, Mediterranean in coastal California and arid in the Great Basin. Its comparatively favorable agricultural climate contributed (in part) to the country's rise as a world power, with infrequent severe drought in the major agricultural regions, a general lack of widespread flooding, and a mainly temperate climate that receives adequate precipitation.???
output answer: severe drought

input question: Extract the answer to the question from the following context. Question: Which of the following is not an example of a dog breed: Chihuahua, Irish Wolfhound, or morphological variation? Context: Most breeds of dog are at most a few hundred years old, having been artificially selected for particular morphologies and behaviors by people for specific functional roles. Through this selective breeding, the dog has developed into hundreds of varied breeds, and shows more behavioral and morphological variation than any other land mammal. For example, height measured to the withers ranges from 15.2 centimetres (6.0 in) in the Chihuahua to about 76 cm (30 in) in the Irish Wolfhound; color varies from white through grays (usually called "blue") to black, and browns from light (tan) to dark ("red" or "chocolate") in a wide variation of patterns; coats can be short or long, coarse-haired to wool-like, straight, curly, or smooth. It is common for most breeds to shed this coat.???
output answer:
morphological variation