Given an trivia question precisely answer the question with a word/phrase/name. External resources such as Wikipedia could be used to obtain the facts.

Q: What is the largest city in India?

A: calcutta
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Q: What note is produced at the twelfth fret of the top (highest pitched) string on a conventionally tuned guitar?

A: e
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Q: 'Dr. Robotnik' and 'Knuckles the Echidna' are characters in which video game series?

A:
sonic the hedgehog
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