Answer: B. The Blackburn Committee decide which student is the most qualified and most deserves the Covington Scholarship.
Explanation: 'decide' is not meant to be in this sentence as it doesn't make any sense. Instead, it would be best to replace the word 'decide' with 'decides'. Since 'The Blackburn Committee' is most likely not singular, you have to use a plural verb. A subject-verb agreement is exactly this, making sure the subject and verb are matching, both singular, both plural, both present, both past, that sort of thing.
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