A question that is free of any grammatical or logcal errors, should be labeled 'yes', otherwise it should be indicated as 'no'. A question is grammatically correct if all its entities i.e. nouns, verbs, adjectives, prepositions, pronouns, adverbs are at appropriate position. A question is logically correct if the semantic makes sense.

Q: Sentence: With large population movements in the 1990s to urban areas, the provision of education has undergone transformation as well.
Question: How long of a time do we refer to when we say ""the 1990s""?

A: No.
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Q: Sentence: In Colombia, the drug-financed guerrillas trying to seize the country and destroy democracy include M-19, which Castro has clearly backed.
Question: How long had the guerillas been supported by Castro?

A: Yes.
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Q: Sentence: With this, it became impossible for me to stay upstairs, he said, pointing to the scars on his forearm.
Question: When did he get his scars?

A:
No.
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