Use a disfluent question or a proper question and find the answer to the question based on the given context or return None if an answer can't be found. A disfluent question is a question that has some interruptions in it while framing. A proper question is the correct form of the question without any disfluency.

Q: proper question: What are clades? 
 disfluent question: clades are described as what? 
 context: The study also found that there were two previously unknown but related clades (genetic branches) of the Y. pestis genome associated with medieval mass graves. These clades (which are thought to be extinct) were found to be ancestral to modern isolates of the modern Y. pestis strains Y. p. orientalis and Y. p. medievalis, suggesting the plague may have entered Europe in two waves. Surveys of plague pit remains in France and England indicate the first variant entered Europe through the port of Marseille around November 1347 and spread through France over the next two years, eventually reaching England in the spring of 1349, where it spread through the country in three epidemics. Surveys of plague pit remains from the Dutch town of Bergen op Zoom showed the Y. pestis genotype responsible for the pandemic that spread through the Low Countries from 1350 differed from that found in Britain and France, implying Bergen op Zoom (and possibly other parts of the southern Netherlands) was not directly infected from England or France in 1349 and suggesting a second wave of plague, different from those in Britain and France, may have been carried to the Low Countries from Norway, the Hanseatic cities or another site.

A: genetic branches
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Q: proper question: What is one work by Neumes? 
 disfluent question: What is one work by Messiaen oh sorry, by Neumes? 
 context: Prime numbers have influenced many artists and writers. The French composer Olivier Messiaen used prime numbers to create ametrical music through natural phenomena. In works such as La Nativité du Seigneur (1935) and Quatre études de rythme (1949–50), he simultaneously employs motifs with lengths given by different prime numbers to create unpredictable rhythms: the primes 41, 43, 47 and 53 appear in the third étude, Neumes rythmiques. According to Messiaen this way of composing was inspired by the movements of nature, movements of free and unequal durations.

A: None
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Q: proper question: Where did Marin build first fort? 
 disfluent question: Where did Marin design or I meant build his first fort? 
 context: In the spring of 1753, Paul Marin de la Malgue was given command of a 2,000-man force of Troupes de la Marine and Indians. His orders were to protect the King's land in the Ohio Valley from the British. Marin followed the route that Céloron had mapped out four years earlier, but where Céloron had limited the record of French claims to the burial of lead plates, Marin constructed and garrisoned forts. He first constructed Fort Presque Isle (near present-day Erie, Pennsylvania) on Lake Erie's south shore. He had a road built to the headwaters of LeBoeuf Creek. Marin constructed a second fort at Fort Le Boeuf (present-day Waterford, Pennsylvania), designed to guard the headwaters of LeBoeuf Creek. As he moved south, he drove off or captured British traders, alarming both the British and the Iroquois. Tanaghrisson, a chief of the Mingo, who were remnants of Iroquois and other tribes who had been driven west by colonial expansion. He intensely disliked the French (whom he accused of killing and eating his father). Traveling to Fort Le Boeuf, he threatened the French with military action, which Marin contemptuously dismissed.

A:
near present-day Erie, Pennsylvania
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