Scientists have recently found evidence that black holes—regions of space in which matter is so concentrated and the pull of gravity so powerful that nothing, not even light, can emerge from them—probably exist at the core of nearly all galaxies and the mass of each black hole is proportional to its host galaxy.
A. exist at the core of nearly all galaxies and the mass of each black hole is proportional to
B. exist at the core of nearly all galaxies and that the mass of each black hole is proportional to that of
C. exist at the core of nearly all galaxies, and that the mass of each black hole is proportional to
D. exists at the core of nearly all galaxies, and that the mass of each black hole is proportional to that of
E. exists at the core of nearly all galaxies and the mass of each black hole is proportional to that of
In-depth Explanation and Correct Answer Below (so you don’t see it while reviewing the question)
Scientists have recently found evidence that black holes… Explanation
Scientists have recently found evidence that black holes—regions of space in which matter is so concentrated and the pull of gravity so powerful that nothing, not even light, can emerge from them—probably exist at the core of nearly all galaxies and the mass of each black hole is proportional to its host galaxy.
(A) exist at the core of nearly all galaxies and the mass of each black hole is proportional to
Parallelism is off. Scientists have found evidence THAT X and THAT Y. If you have a that or a which in front of one of your items then you likely need it in front of the other. The items need to match.
(B) exist at the core of nearly all galaxies and that the mass of each black hole is proportional to that of
“That” replaces mass so we have a parallel Mass to Mass comparison.
(C) exist at the core of nearly all galaxies, and that the mass of each black hole is proportional to
We need a parallel comparison (compare like things). Black hole to Galaxy or Mass to Mass. Here we are comparing Mass to Galaxy.
(D) exists at the core of nearly all galaxies, and that the mass of each black hole is proportional to that of
Subject verb agreement. Black holes exist.
(E) exists at the core of nearly all galaxies and the mass of each black hole is proportional to that of
Subject verb agreement. Black holes exist. Also, parallelism is off. Scientists have found evidence THAT X and THAT Y. If you have a that or a which in front of one of your items then you likely need it in front of the other. The items need to match.
Correct Answer: B
For some SC guidance, here’s a link to a breakdown of GMAT sentence correction.