Thanks everyone for their overwhelming participation in this question. Here is the much awaited solution!
Apple, the company that has the highest revenue per employee, focuses
more on simplistic and functional design than its competitors.

• Apple, the company
• that has the highest revenue per employee,
• focuses
more on simplistic and functional design than its competitors.
The sentence presents a comparison. However, the way this sentence is written, one can infer two comparisons:
o Apple focusses more on simplistic and functional design than on its competitors. The entities compared are simplistic and functional design and competitors.
o Apple focusses more on simplistic and functional design than its competitors focus on. The entities compared are Apple and its competitors.
The correct sentence should clearly state one clear meaning.
Error Analysis• Apple, the company
• that has the highest revenue per employee,
• focuses
more on simplistic and functional design than its competitors.
If the sentence is intended to compare simplistic and functional design and competitors (stating that Apple focuses on design more than it focuses on its competitors), then we need the pronoun “on” before “its competitors” to make the comparison clear.
If the sentence is intended to compare Apple and its competitors (stating that Apple focuses on design more than its competitors do), then we need the helping verb “do” before “its competitors” to make the comparison clear.
PoEA. more on simplistic and functional design than
Incorrect for the reasons stated above.
B. on more simplistic yet functional design than:
Incorrect.Error 1 – Repeats the same ambiguous comparison error as in choice A.
Error 2 – Change of placement of “more” changes the meaning. Per the original sentence, “more” modifies “focusses”. Apple focusses more on design than its competitors. Per this choice, “more” modifies “simplistic design”. Here the emphasis is not the action of focusing but on the design itself.
Error 3 – Use of “yet” changes the meaning. Per the original choice, “and” suggests that the design is simple and functional. Use of word “yet” brings in the contrast, implying that even though the design is simple, it is functional. The original sentence does not present this contrast.
C. more on simplistic and functional design than on:
Correct AnswerUse of preposition “on” makes the comparison clear. The sentence states that Apple focusses on design more than it focuses on its competitors.
D. on simplistic and functional design than:
Incorrect.Error 1 – Use of “than” requires the use of some comparative terms such as “more” to present comparison. Just using “than” leads to idiom error in this choice.
Error 2 – Repeats the same ambiguous comparison error as in choice A.
E. more on simplistic design and is more functional than are:
Incorrect.Error 1 – This choice distorts the intended meaning. Per this choice, the subject for “is” is
“Apple”. The choice suggests that Apple is more functional whereas, per the original choice, the design is functional. Also the choice suggests comparison between Apple and the competitors on the basis that Apple is more functional. This is certainly not the intended meaning of the sentence

1. The sentence must be constructed in such a way that the comparison is absolutely clear. As we saw in this case due to omission of words, the comparison was no longer clear. So when we omit words we should always make sure that the comparison does not become unclear.
2. Pay attention to the change in placement of the words. Such changes in placement may lead to change in the intended meaning of the sentence.
3. Be wary of the choices that distort the intended meaning of the sentence.
Thanks.

Payal
Can't 'do' be missing because of usage of ellipsis as mentioned in my post below: