GMAT Sentence Correction (SC) | Re: Although a surge in retail sales have raised hopes that

Although a surge in retail sales have raised hopes that there is a recovery finally under way, many economists say that without a large amount of spending the recovery might not last.

The sentence starts with 'although' which shows that there will be a contrast in the sentence.
'Surge' is the subject and is singular. Therefore its verb must be singular i.e. has raised.

Option D corrects this error. Rest is fine.

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