Correct the following sentence.
the steel industry has changed radically over the last two decades, as large, integrated companies such as bethlehem steel once conducted operations from mining at one end of the process to shipping at the other have greatly downsized, or in some cases shut down altogether.(a) as large, integrated companies such as bethlehem steel(b) as large, integrated companies, such as bethlehem steel, that(c) with large, integrated companies, such as bethlehem steel, that(d) while large, integrated companies, such as bethlehem steel, that(e) and large, integrated companies such as bethlehem steel

The best option to correct the sentence is letter B) as large, integrated companies, such as Bethlehem Steel, that

Explanation:

Letter A doesn't really change anything in the sentence. Letters C, D and E change "as" for "with", "while",  and "and" unnecessarily, since the problem is not related to the word "as" at all.

The issue with the original sentence is mainly punctuation and ambiguity. For a moment, we think the information that comes after the name "Bethlehem Steel" refers to it. Only after a careful reading do we realize that it does not. The information beginning with "once conducted..." refers to "companies". What makes it even clearer is the plural verb "have" showing up later in the sentence, not agreeing with "Bethlehem Steel", but with "companies" instead. Therefore, to make that clear, the best option is letter B. It uses proper punctuation and ads a "that" to make sure readers understand to which subject the information refers.

The steel industry has changed radically over the last two decades, as large, integrated companies, such as Bethlehem Steel, that once conducted operations from mining at one end of the process to shipping at the other have greatly downsized, or in some cases shut down altogether.