Sentence Correction (SC) | Re: Although dark matter was first postulated in 1932 to account for the o

A) it did not drive the discovery of more information about it to be done by astrophysicists until it was the 1990s

Dark Matter did not drive.... about dark matter... by A, until "it" (placeholder) was 1990s. Why do we need so many its to represent dark matter? A GMAT sentence correction can convey the meaning in more precise way.

B) it was not until the 1990s that astrophysicists were driven to discover more information about it

The first it is a placeholder, the 2nd one refers back
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