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:
In 1869 the Suez Canal opened under Napoleon III, linking the Mediterranean with the Indian Ocean. Initially the Canal was opposed by the British; but once opened, its strategic value was quickly recognised and became the "jugular vein of the Empire". In 1875, the Conservative government of Benjamin Disraeli bought the indebted Egyptian ruler Isma'il Pasha's 44 percent shareholding in the Suez Canal for £4 million (£340 million in 2013). Although this did not grant outright control of the strategic waterway, it did give Britain leverage. Joint Anglo-French financial control over Egypt ended in outright British occupation in 1882. The French were still majority shareholders and attempted to weaken the British position, but a compromise was reached with the 1888 Convention of Constantinople, which made the Canal officially neutral territory.
answer:
When did the Suez Canal open?


question:
In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in a glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the USA, changed his name to Alexander de Lodyguine and applied and obtained patents for incandescent lamps having chromium, iridium, rhodium, ruthenium, osmium, molybdenum and tungsten filaments, and a bulb using a molybdenum filament was demonstrated at the world fair of 1900 in Paris.
answer:
Who patented an incandescent light bulb in Russia in 1874?


question:
On January 13, 1887, the U,S. Government moved to annul the patent issued to Bell on the grounds of fraud and misrepresentation. After a series of decisions and reversals, the Bell company won a decision in the Supreme Court, though a couple of the original claims from the lower court cases were left undecided. By the time that the trial wound its way through nine years of legal battles, the U.S. prosecuting attorney had died and the two Bell patents (No. 174,465 dated March 7, 1876 and No. 186,787 dated January 30, 1877) were no longer in effect, although the presiding judges agreed to continue the proceedings due to the case's importance as a "precedent". With a change in administration and charges of conflict of interest (on both sides) arising from the original trial, the US Attorney General dropped the lawsuit on November 30, 1897 leaving several issues undecided on the merits.
answer:

In 1887 the US Government wanted to undo Bell's patent due to fraud and what?