Sentence Correction

The process of digital remastering is the method by which analog sound recordings are
converted to digital files, edited to remove undesirable audio artifacts introduced during analog
recording, and filtered to enhance the overall quality of the sound.

(a) The process of digital remastering is the method by which analog sound recordings are
converted to digital files
(b) The process of digital remastering is the way that analog sound recordings are converted to
digital files
(c) Digital remastering is the process by which analog sound recordings are converted to digital
files
(d) Digital remastering occurs when analog sound recordings are converted to digital files
(e) Digital remastering, the process by which analog sound recordings are converted to digital files

can anyone help me out with the answer here? Thank you for your response