In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: What channel claimed that there had once been a civilization in the Amazon rainforest?, Context: The first European to travel the length of the Amazon River was Francisco de Orellana in 1542. The BBC's Unnatural Histories presents evidence that Orellana, rather than exaggerating his claims as previously thought, was correct in his observations that a complex civilization was flourishing along the Amazon in the 1540s. It is believed that the civilization was later devastated by the spread of diseases from Europe, such as smallpox. Since the 1970s, numerous geoglyphs have been discovered on deforested land dating between AD 0–1250, furthering claims about Pre-Columbian civilizations. Ondemar Dias is accredited with first discovering the geoglyphs in 1977 and Alceu Ranzi with furthering their discovery after flying over Acre. The BBC's Unnatural Histories presented evidence that the Amazon rainforest, rather than being a pristine wilderness, has been shaped by man for at least 11,000 years through practices such as forest gardening and terra preta.

Answer: BBC


Question: What does research show about sexual orientation?, Context: Scientists do not know the exact cause of sexual orientation, but they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences. They favor biologically-based theories, which point to genetic factors, the early uterine environment, both, or the inclusion of genetic and social factors. There is no substantive evidence which suggests parenting or early childhood experiences play a role when it comes to sexual orientation. Research over several decades has demonstrated that sexual orientation ranges along a continuum, from exclusive attraction to the opposite sex to exclusive attraction to the same sex.

Answer: they believe that it is caused by a complex interplay of genetic, hormonal, and environmental influences


Question: Above where was Powers flying when he was shot down?, Context: On May 1, 1960, a U.S. one-man U-2 spy plane was reportedly shot down at high altitude over Soviet Union airspace. The flight was made to gain photo intelligence before the scheduled opening of an East–West summit conference, which had been scheduled in Paris, 15 days later. Captain Francis Gary Powers had bailed out of his aircraft and was captured after parachuting down onto Russian soil. Four days after Powers disappeared, the Eisenhower Administration had NASA issue a very detailed press release noting that an aircraft had "gone missing" north of Turkey. It speculated that the pilot might have fallen unconscious while the autopilot was still engaged, and falsely claimed that "the pilot reported over the emergency frequency that he was experiencing oxygen difficulties."

Answer:
Soviet Union airspace