GMAT Strategy

I am not sure whether this i can post SC questions in this forum (even thoug we have a dedicated one for SC)

In its most recent approach, the comet Crommelin passed the Earth at about the same distance and in about the same position, some 25 degrees above the horizon, that Halley’s comet will pass the next time it appears.
(A) that Halley’s comet will pass
(B) that Halley’s comet is to be passing
(C) as Halley’s comet
(D) as will Halley’s comet
(E) as Halley’s comet will do

I was able to zero in on A and D, but went ahead with A. But the answer is D.

In this case why was D preferred over A? Is it due to conciseness or any other grammatical issue?