TASK DEFINITION: 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.
PROBLEM: The Ottoman Empire or, as a dynastic institution, the House of Osman was unprecedented and unequaled in the Islamic world for its size and duration. In Europe, only the House of Habsburg had a similarly unbroken line of sovereigns (kings/emperors) from the same family who ruled for so long, and during the same period, between the late 13th and early 20th centuries. The Ottoman dynasty was Turkish in origin. On eleven occasions, the sultan was deposed (replaced by another sultan of the Ottoman dynasty, who were either the former sultan's brother, son or nephew) because he was perceived by his enemies as a threat to the state. There were only two attempts in Ottoman history to unseat the ruling Ottoman dynasty, both failures, which suggests a political system that for an extended period was able to manage its revolutions without unnecessary instability. As such, the last Ottoman sultan Mehmed VI (r. 1918–1922) was a direct patrilineal (male-line) descendant of the first Ottoman sultan Osman I (r. 1299–1326), which was unparallelled in both Europe (e.g. the male line of the House of Habsburg became extinct in 1740) and in the Islamic world. The primary purpose of the Imperial Harem was to ensure the birth of male heirs to the Ottoman throne and secure the continuation of the direct patrilineal (male-line) descendance of the Ottoman sultans.

SOLUTION: What was another name for the Ottoman Empire?

PROBLEM: However a log-periodic dipole array consists of a number of dipole elements of different lengths in order to obtain a somewhat directional antenna having an extremely wide bandwidth: these are frequently used for television reception in fringe areas. The dipole antennas composing it are all considered "active elements" since they are all electrically connected together (and to the transmission line). On the other hand, a superficially similar dipole array, the Yagi-Uda Antenna (or simply "Yagi"), has only one dipole element with an electrical connection; the other so-called parasitic elements interact with the electromagnetic field in order to realize a fairly directional antenna but one which is limited to a rather narrow bandwidth. The Yagi antenna has similar looking parasitic dipole elements but which act differently due to their somewhat different lengths. There may be a number of so-called "directors" in front of the active element in the direction of propagation, and usually a single (but possibly more) "reflector" on the opposite side of the active element.

SOLUTION: What type of antenna formation is made up of multiple dipole elements of varying lengths?

PROBLEM: Although the firearms used by the infantry, particularly machine guns, can be used to engage low altitude air targets, on occasion with notable success, their effectiveness is generally limited and the muzzle flashes reveal infantry positions. Speed and altitude of modern jet aircraft limit target opportunities, and critical systems may be armored in aircraft designed for the ground attack role. Adaptations of the standard autocannon, originally intended for air-to-ground use, and heavier artillery systems were commonly used for most anti-aircraft gunnery, starting with standard pieces on new mountings, and evolving to specially designed guns with much higher performance prior to World War II.

SOLUTION:
What did the muzzle flashes of the firearms used by the infantry reveal?