instruction:
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.
question:
However, Lok-Ham Chan, a professor of history at the University of Washington, writes that Changchub Gyaltsen's aims were to recreate the old Tibetan Kingdom that existed during the Chinese Tang dynasty, to build "nationalist sentiment" amongst Tibetans, and to "remove all traces of Mongol suzerainty." Georges Dreyfus, a professor of religion at Williams College, writes that it was Changchub Gyaltsen who adopted the old administrative system of Songtsän Gampo (c. 605–649)—the first leader of the Tibetan Empire to establish Tibet as a strong power—by reinstating its legal code of punishments and administrative units. For example, instead of the 13 governorships established by the Mongol Sakya viceroy, Changchub Gyaltsen divided Central Tibet into districts (dzong) with district heads (dzong dpon) who had to conform to old rituals and wear clothing styles of old Imperial Tibet. Van Praag asserts that Changchub Gyaltsen's ambitions were to "restore to Tibet the glories of its Imperial Age" by reinstating secular administration, promoting "national culture and traditions," and installing a law code that survived into the 20th century.
answer:
Who divided Central Tibet into districts? 


question:
When the GHMC was created in 2007, the area occupied by the municipality increased from 175 km2 (68 sq mi) to 650 km2 (250 sq mi). Consequently, the population increased by 87%, from 3,637,483 in the 2001 census to 6,809,970 in the 2011 census, 24% of which are migrants from elsewhere in India,:2 making Hyderabad the nation's fourth most populous city. As of 2011[update], the population density is 18,480/km2 (47,900/sq mi). At the same 2011 census, the Hyderabad Urban Agglomeration had a population of 7,749,334, making it the sixth most populous urban agglomeration in the country. The population of the Hyderabad urban agglomeration has since been estimated by electoral officials to be 9.1 million as of early 2013 but is expected to exceed 10 million by the end of the year. There are 3,500,802 male and 3,309,168 female citizens—a sex ratio of 945 females per 1000 males, higher than the national average of 926 per 1000. Among children aged 0–6 years, 373,794 are boys and 352,022 are girls—a ratio of 942 per 1000. Literacy stands at 82.96% (male 85.96%; female 79.79%), higher than the national average of 74.04%. The socio-economic strata consist of 20% upper class, 50% middle class and 30% working class.
answer:
What was the area of Hyderabad before the GHMC?


question:
Regression testing focuses on finding defects after a major code change has occurred. Specifically, it seeks to uncover software regressions, as degraded or lost features, including old bugs that have come back. Such regressions occur whenever software functionality that was previously working correctly, stops working as intended. Typically, regressions occur as an unintended consequence of program changes, when the newly developed part of the software collides with the previously existing code. Common methods of regression testing include re-running previous sets of test-cases and checking whether previously fixed faults have re-emerged. The depth of testing depends on the phase in the release process and the risk of the added features. They can either be complete, for changes added late in the release or deemed to be risky, or be very shallow, consisting of positive tests on each feature, if the changes are early in the release or deemed to be of low risk. Regression testing is typically the largest test effort in commercial software development, due to checking numerous details in prior software features, and even new software can be developed while using some old test-cases to test parts of the new design to ensure prior functionality is still supported.
answer:

Finding defects once a change in code had already happened is called?