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.
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Question: The primary physiological cue for migration are the changes in the day length. These changes are also related to hormonal changes in the birds. In the period before migration, many birds display higher activity or Zugunruhe (German: migratory restlessness), first described by Johann Friedrich Naumann in 1795, as well as physiological changes such as increased fat deposition. The occurrence of Zugunruhe even in cage-raised birds with no environmental cues (e.g. shortening of day and falling temperature) has pointed to the role of circannual endogenous programs in controlling bird migrations. Caged birds display a preferential flight direction that corresponds with the migratory direction they would take in nature, changing their preferential direction at roughly the same time their wild conspecifics change course.

Answer: What is the primary cue for migration?

Question: The Continental Army was created on 14 June 1775 by the Continental Congress as a unified army for the colonies to fight Great Britain, with George Washington appointed as its commander. The army was initially led by men who had served in the British Army or colonial militias and who brought much of British military heritage with them. As the Revolutionary War progressed, French aid, resources, and military thinking influenced the new army. A number of European soldiers came on their own to help, such as Friedrich Wilhelm von Steuben, who taught the army Prussian tactics and organizational skills.

Answer: When was the Continental Army created?

Question: After a trend of declining population density since World War II, the city has seen increased density in the inner and western suburbs, aided in part by Victorian Government planning, such as Postcode 3000 and Melbourne 2030 which have aimed to curtail urban sprawl. According to the Australian Bureau of Statistics as of June 2013, inner city Melbourne had the highest population density with 12,400 people per km2. Surrounding inner city suburbs experienced an increase in population density between 2012 and 2013; Carlton (9,000 people per km2) and Fitzroy (7,900).

Answer:
What have Postcode 3000 and Melbourne 2030 aimed to do?