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.

Q: Passage: Michael Lynche was the lowest vote getter at top nine and was given the Judges' Save. The next week Katie Stevens and Andrew Garcia were eliminated. That week, Adam Lambert was invited back to be a mentor, the first Idol alum to do so. Idol Gives Back returned this season on April 21, 2010, and raised $45 million. Question: Who was the first American Idol contestant to return to the show as a mentor?

A: Adam Lambert
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Q: Passage: The MC controls the conferencing while it is active on the signaling plane, which is simply where the system manages conferencing creation, endpoint signaling and in-conferencing controls. This component negotiates parameters with every endpoint in the network and controls conferencing resources. While the MC controls resources and signaling negotiations, the MP operates on the media plane and receives media from each endpoint. The MP generates output streams from each endpoint and redirects the information to other endpoints in the conference. Question: What controls the conferencing while its active on the signaling plane?

A: The MC
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Q: Passage: The official English name of the system is BeiDou Navigation Satellite System. It is named after the Big Dipper constellation, which is known in Chinese as Beidou. The name literally means "Northern Dipper", the name given by ancient Chinese astronomers to the seven brightest stars of the Ursa Major constellation. Historically, this set of stars was used in navigation to locate the North Star Polaris. As such, the name BeiDou also serves as a metaphor for the purpose of the satellite navigation system. Question: What was the Beidou constellation used for?

A:
to locate the North Star Polaris
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