Official Solution:
In her most recent press conference, the CEO declared that although it had not expanded its production capacities, the company had not only more efficient assembly lines than before, it also had faster packaging machines, that had reduced the cost of manufacturing by 16%.
A. more efficient assembly lines than before, it also had faster packaging machines, that had reduced the
B. assembly lines that were more efficient than before, but it also had faster packaging machines, resulting in a reduction in the
C. assembly lines that were more efficient than before, but had faster packaging machines also, reducing the
D. more efficient assembly lines than before, but also faster packaging machines, resulting in a reduced
E. assembly lines that were more efficient than before, but also faster packaging machines, reducing the
A. Faulty parallelism structure - “Not only” is followed by a noun phrase “more efficient assembly lines”, but the second element consists of the verb “had”. A verb and a noun phrase cannot be parallel.
The expression “more efficient assembly lines than before” does not clarify whether there were a higher number of assembly lines (that were equally efficient) than before or the same number of assembly lines that were more efficient than before. This construction has two possible meanings and hence is ambiguous.
The modifier “that had reduced…” wrongly refers to packaging machines, whereas it is intended to express that having assembly lines more efficient than before (or more assembly lines that are efficient) and faster packing machines had reduced the cost of manufacturing.
B. Faulty parallelism structure - “Not only” is followed by a noun phrase “more efficient assembly lines”, but the second element consists of the verb “had”. A verb and a noun phrase cannot be parallel.
C. Faulty parallelism structure - “Not only” is followed by a noun phrase “more efficient assembly lines”, but the second element consists of the verb “had”. A verb and a noun phrase cannot be parallel.
D. The expression “more efficient assembly lines than before” does not clarify whether there were a higher number of assembly lines (that were equally efficient) than before or the same number of assembly lines that were more efficient than before. This construction has two possible meanings and hence is ambiguous.
The expression “…resulting in a reduced cost..by 16%” is awkward. Better is “..resulting in a reduction in cost…by 16%.”
E. ORRECT. Corrects all the errors above.
Answer: E