This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

[EX Q]: Up to the 1990s, the Federal District was the most populous federal entity in Mexico, but since then its population has remained stable at around 8.7 million. The growth of the city has extended beyond the limits of the Federal District to 59 municipalities of the state of Mexico and 1 in the state of Hidalgo. With a population of approximately 19.8 million inhabitants (2008), it is one of the most populous conurbations in the world. Nonetheless, the annual rate of growth of the Metropolitan Area of Mexico City is much lower than that of other large urban agglomerations in Mexico, a phenomenon most likely attributable to the environmental policy of decentralization. The net migration rate of the Federal District from 1995 to 2000 was negative.
[EX A]: How many people live in the Federal District? 

[EX Q]: Many ancient civilizations alloyed metals for purely aesthetic purposes. In ancient Egypt and Mycenae, gold was often alloyed with copper to produce red-gold, or iron to produce a bright burgundy-gold. Gold was often found alloyed with silver or other metals to produce various types of colored gold. These metals were also used to strengthen each other, for more practical purposes. Copper was often added to silver to make sterling silver, increasing its strength for use in dishes, silverware, and other practical items. Quite often, precious metals were alloyed with less valuable substances as a means to deceive buyers. Around 250 BC, Archimedes was commissioned by the king to find a way to check the purity of the gold in a crown, leading to the famous bath-house shouting of "Eureka!" upon the discovery of Archimedes' principle.
[EX A]: Ancient civilizations often alloyed metals for what reason?

[EX Q]: The route carried the torch through six continents from March 2008 to May 2008 to August 2008. The planned route originally included a stop in Taipei between Ho Chi Minh City and Hong Kong, but there was disagreement in Beijing and Taipei over language used to describe whether it was an international or a domestic part of the route. While the Olympic committees of China and Chinese Taipei reached initial consensus on the approach, the government of the Republic of China in Taiwan intervened, stating that this placement could be interpreted as placing Taiwan on the same level as Hong Kong and Macau, an implication it objected to. The Beijing Organizing Committee attempted to continue negotiation, but further disputes arose over the flag or the anthem of the Republic of China along the 24 km torch route in Taiwan. By the midnight deadline for concluding the negotiation on September 21, 2007, Taiwan and China were unable to come to terms with the issue of the Torch Relay. In the end, both sides of the Taiwan Strait decided to eliminate the Taipei leg.
[EX A]:
How many continents did the torch visit?