Pardon my lingering on this stupid question but it's annoying the hell outta me. What about "from corrosion" at the end.
so "now require protection from corrosion as they are made of ungalvanized wire protection from corrosion".
You're right, the underlined part is being replaced. I think this sentence could be corrected very easily. See the comma before "those".
How could C be correct? I thought about how this would work when I first saw the question but the complete sentence would be:
Unlike the main cables of most suspension bridges, those of the eighty-year-old Williamsburg Bridge now require protection from corrosion as they are made of ungalvanized wire protection from corrosion.
I mean it's a little technical but isn't the underlined part being replaced? Makes for a wordy and confusing sentence...