In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Ex Input:
Why could there be reasonable doubt about the validity of what was stated that she said?, Context: In May 2007, The Daily Telegraph, citing unnamed sources, reported that the Queen was "exasperated and frustrated" by the policies of the British Prime Minister, Tony Blair, that she was concerned the British Armed Forces were overstretched in Iraq and Afghanistan, and that she had raised concerns over rural and countryside issues with Blair. She was, however, said to admire Blair's efforts to achieve peace in Northern Ireland. On 20 March 2008, at the Church of Ireland St Patrick's Cathedral, Armagh, the Queen attended the first Maundy service held outside England and Wales. At the invitation of the Irish President, Mary McAleese, the Queen made the first state visit to the Republic of Ireland by a British monarch in May 2011.

Ex Output:
unnamed sources

Ex Input:
Who lost their majority in parliament?, Context: The 1923 general election was fought on the Conservatives' protectionist proposals but, although they got the most votes and remained the largest party, they lost their majority in parliament, necessitating the formation of a government supporting free trade. Thus, with the acquiescence of Asquith's Liberals, Ramsay MacDonald became the first ever Labour Prime Minister in January 1924, forming the first Labour government, despite Labour only having 191 MPs (less than a third of the House of Commons).

Ex Output:
Conservatives

Ex Input:
What should I try my best to avoid if I want to facilitate organomagnesium halide?, Context: There are many important organozinc compounds. Organozinc chemistry is the science of organozinc compounds describing their physical properties, synthesis and reactions. Among important applications is the Frankland-Duppa Reaction in which an oxalate ester(ROCOCOOR) reacts with an alkyl halide R'X, zinc and hydrochloric acid to the -hydroxycarboxylic esters RR'COHCOOR, the Reformatskii reaction which converts -halo-esters and aldehydes to -hydroxy-esters, the SimmonsSmith reaction in which the carbenoid (iodomethyl)zinc iodide reacts with alkene(or alkyne) and converts them to cyclopropane, the Addition reaction of organozinc compounds to carbonyl compounds. The Barbier reaction (1899) is the zinc equivalent of the magnesium Grignard reaction and is better of the two. In presence of just about any water the formation of the organomagnesium halide will fail, whereas the Barbier reaction can even take place in water. On the downside organozincs are much less nucleophilic than Grignards, are expensive and difficult to handle. Commercially available diorganozinc compounds are dimethylzinc, diethylzinc and diphenylzinc. In one study the active organozinc compound is obtained from much cheaper organobromine precursors:

Ex Output:
water