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.

[Q]: Karlheinz Brandenburg used a CD recording of Suzanne Vega's song "Tom's Diner" to assess and refine the MP3 compression algorithm. This song was chosen because of its nearly monophonic nature and wide spectral content, making it easier to hear imperfections in the compression format during playbacks. Some refer to Suzanne Vega as "The mother of MP3". This particular track has an interesting property in that the two channels are almost, but not completely, the same, leading to a case where Binaural Masking Level Depression causes spatial unmasking of noise artifacts unless the encoder properly recognizes the situation and applies corrections similar to those detailed in the MPEG-2 AAC psychoacoustic model. Some more critical audio excerpts (glockenspiel, triangle, accordion, etc.) were taken from the EBU V3/SQAM reference compact disc and have been used by professional sound engineers to assess the subjective quality of the MPEG Audio formats.
[A]: What type of recording did Brandenburg use?


[Q]: The rapid increase of population of A Coruña, Vigo and to a lesser degree other major Galician cities, like Ourense, Pontevedra or Santiago de Compostela during the years that followed the Spanish Civil War during the mid-20th century occurred as the rural population declined: many villages and hamlets of the four provinces of Galicia disappeared or nearly disappeared during the same period. Economic development and mechanization of agriculture resulted in the fields being abandoned, and most of the population has moving to find jobs in the main cities. The number of people working in the Tertiary and Quaternary sectors of the economy has increased significantly.
[A]: A rapid population growth after occurred after which war?


[Q]: The establishment of Ottoman military aviation dates back to between June 1909 and July 1911. The Ottoman Empire started preparing its first pilots and planes, and with the founding of the Aviation School (Tayyare Mektebi) in Yeşilköy on 3 July 1912, the Empire began to tutor its own flight officers. The founding of the Aviation School quickened advancement in the military aviation program, increased the number of enlisted persons within it, and gave the new pilots an active role in the Ottoman Army and Navy. In May 1913 the world's first specialized Reconnaissance Training Program was started by the Aviation School and the first separate reconnaissance division was established.[citation needed] In June 1914 a new military academy, the Naval Aviation School (Bahriye Tayyare Mektebi) was founded. With the outbreak of World War I, the modernization process stopped abruptly. The Ottoman aviation squadrons fought on many fronts during World War I, from Galicia in the west to the Caucasus in the east and Yemen in the south.
[A]:
What was the first date that the Ottoman empire had an air-based military unit?