This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
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Question: Passage: In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential. Question: What property of T cells caused modification of CST?

Answer: the complex "two-signal" activation


Question: Passage: In 1975, the band left for a world tour with each member in Zandra Rhodes-created costumes and accompanied with banks of lights and effects. They toured the US as headliners, and played in Canada for the first time. In September, after an acromonious split with Trident, the band negotiated themselves out of their Trident Studios contract and searched for new management. One of the options they considered was an offer from Led Zeppelin's manager, Peter Grant. Grant wanted them to sign with Led Zeppelin's own production company, Swan Song Records. The band found the contract unacceptable and instead contacted Elton John's manager, John Reid, who accepted the position. Question: Queen had a bitter split with what management company in 1975?

Answer: Trident Studios


Question: Passage: The Broncos took an early lead in Super Bowl 50 and never trailed. Newton was limited by Denver's defense, which sacked him seven times and forced him into three turnovers, including a fumble which they recovered for a touchdown. Denver linebacker Von Miller was named Super Bowl MVP, recording five solo tackles, 2½ sacks, and two forced fumbles. Question: How many fumbles did Von Miller force?

Answer:
two