Select the word segment that substitutes (replaces) the bracketed word segment correctly and completes the sentence meaningfully. Select the option 'no correction required' if the sentence is correct as given.
Incineration has been used for decades (as the magic-bullet solution to disposing otherwise) persistent waste materials.
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as the magic-bullet solution of disposing otherwise
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No correction required
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as the magic-bullet solution to disposing of otherwise
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as the magic-bullet solution to disposing off otherwise