Sentence Correction (SC) | Working with musician Stevie Wonder as a musical adviser

Working with musician Stevie Wonder as a musical adviser, Ray Kurzweil developed what is now the preferred medium for creating nearly all music for today’s commercial albums, films, and television: a computer-based instrument capable ofreproducing musical sounds of a quality once thought to be possible only on grand pianos and other acoustic instruments.

a) reproducing musical sounds of a quality once thought to be
b) reproducing musical sounds with a quality as were once thought to be
c)
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