gmat_perfect wrote:In no other historical sighting did Halley's Comet cause such a worldwide sensation as did its return in 1910-1911.

(A) did its return in 1910-1911

(B) had its 1910-1911 return

(C) in its return of 1910-1911

(D) its return of 1910-1911 did

(E) its return in 1910-1911

If you go by meaning, The sentence ought to compare "in no other historical sighting" with this sighting. Only one options does that i.e. C

Accurately solving requires understanding what is the intended comparison. We're not comparing comets, or even sightings of the comet. The author seeks to compare the extent to which the comet causes a sensation in the 1910 sighting vs the extent to which it caused a sensation in any other sighting ; this is a comparison of actions.

The 1st non-underlined part (simplified) is "Never did the comet cause such a sensation..." the ideal, parallel comparison would end with "as it caused in 1910". Only answer C provides an even comparison. C is correct.

A, B and D fail to convey that the comet causes the sensation. Instead they imply that the comet's return causes the sensation.

E fails to compare actions.

Another way to see why C is correct is to realize that for parallelism's sake, "in no other sighting" should be compared with "as in the 1910 return". This alone should eliminate most answers.

A much more detailed explanation can be found at GMATPrep Question 2087. To practice similar questions in a timed exercise, set topic='Parallelism, Comparison' and difficulty='700+' in the Drill Generator.

Good luck,
-Patrick