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.

Example Input: A significant modification of Cubism between 1914 and 1916 was signaled by a shift towards a strong emphasis on large overlapping geometric planes and flat surface activity. This grouping of styles of painting and sculpture, especially significant between 1917 and 1920, was practiced by several artists; particularly those under contract with the art dealer and collector Léonce Rosenberg. The tightening of the compositions, the clarity and sense of order reflected in these works, led to its being referred to by the critic Maurice Raynal (fr) as 'crystal' Cubism. Considerations manifested by Cubists prior to the outset of World War I—such as the fourth dimension, dynamism of modern life, the occult, and Henri Bergson's concept of duration—had now been vacated, replaced by a purely formal frame of reference.
Example Output: What did the critic Maurice Raynal begin to refer to Cubism in around 1917-1920?

Example Input: The First British Empire was based on mercantilism, and involved colonies and holdings primarily in North America, the Caribbean, and India. Its growth was reversed by the loss of the American colonies in 1776. Britain made compensating gains in India, Australia, and in constructing an informal economic empire through control of trade and finance in Latin America after the independence of Spanish and Portuguese colonies about 1820. By the 1840s, Britain had adopted a highly successful policy of free trade that gave it dominance in the trade of much of the world. After losing its first Empire to the Americans, Britain then turned its attention towards Asia, Africa, and the Pacific. Following the defeat of Napoleonic France in 1815, Britain enjoyed a century of almost unchallenged dominance and expanded its imperial holdings around the globe. Increasing degrees of internal autonomy were granted to its white settler colonies in the 20th century.
Example Output: What was the first British empire based on?

Example Input: Not all of the Luftwaffe's effort was made against inland cities. Port cities were also attacked to try to disrupt trade and sea communications. In January Swansea was bombed four times, very heavily. On 17 January around 100 bombers dropped a high concentration of incendiaries, some 32,000 in all. The main damage was inflicted on the commercial and domestic areas. Four days later 230 tons was dropped including 60,000 incendiaries. In Portsmouth Southsea and Gosport waves of 150 bombers destroyed vast swaths of the city with 40,000 incendiaries. Warehouses, rail lines and houses were destroyed and damaged, but the docks were largely untouched.
Example Output:
Why were port cities targeted by the Luftwaffe?