[Q]: Extract the answer to the question from the following context. Question: What were Hopkins and Willcock trying to do to dietetic factors? Context: In the early 20th century, Carl von Voit and Max Rubner independently measured caloric energy expenditure in different species of animals, applying principles of physics in nutrition. In 1906, Edith G. Willcock and Frederick Hopkins showed that the amino acid tryptophan aids the well-being of mice but it did not assure their growth. In the middle of twelve years of attempts to isolate them, Hopkins said in a 1906 lecture that "unsuspected dietetic factors," other than calories, protein, and minerals, are needed to prevent deficiency diseases. In 1907, Stephen M. Babcock and Edwin B. Hart conducted the single-grain experiment, which took nearly four years to complete.
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[A]: isolate them


[Q]: Extract the answer to the question from the following context. Question: Who was at fault for school segregation? Context: On August 18, 1970, the NAACP filed suit against Michigan state officials, including Governor William Milliken, charging de facto public school segregation. The NAACP argued that although schools were not legally segregated, the city of Detroit and its surrounding counties had enacted policies to maintain racial segregation in public schools. The NAACP also suggested a direct relationship between unfair housing practices and educational segregation, which followed segregated neighborhoods. The District Court held all levels of government accountable for the segregation in its ruling. The Sixth Circuit Court affirmed some of the decision, holding that it was the state's responsibility to integrate across the segregated metropolitan area. The U.S. Supreme Court took up the case February 27, 1974. The subsequent Milliken v. Bradley decision had wide national influence. In a narrow decision, the Court found that schools were a subject of local control and that suburbs could not be forced to solve problems in the city's school district.
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[A]: all levels of government


[Q]: Extract the answer to the question from the following context. Question: What happens when no inner ceremony conveys new secrets? Context: The bulk of Masonic ritual consists of degree ceremonies. Candidates for Freemasonry are progressively initiated into Freemasonry, first in the degree of Entered Apprentice. Some time later, in a separate ceremony, they will be passed to the degree of Fellowcraft, and finally they will be raised to the degree of Master Mason. In all of these ceremonies, the candidate is entrusted with passwords, signs and grips peculiar to his new rank. Another ceremony is the annual installation of the Master and officers of the Lodge. In some jurisdictions Installed Master is valued as a separate rank, with its own secrets to distinguish its members. In other jurisdictions, the grade is not recognised, and no inner ceremony conveys new secrets during the installation of a new Master of the Lodge.
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[A]: the grade is not recognised


[Q]: Extract the answer to the question from the following context. Question: What is crystal pickups an alternative to? Context: Eventually, when it was more common for electric recordings to be played back electrically in the 1930s and 1940s, the overall tone was much like listening to a radio of the era. Magnetic pickups became more common and were better designed as time went on, making it possible to improve the damping of spurious resonances. Crystal pickups were also introduced as lower cost alternatives. The dynamic or moving coil microphone was introduced around 1930 and the velocity or ribbon microphone in 1932. Both of these high quality microphones became widespread in motion picture, radio, recording, and public address applications.
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[A]:
Magnetic pickups