particles that X and Y
Particles here is the subject of the and conjunction:
X : that comprise the atoms and molecules created in the progenitive explosion
Y: persisting in even the emptiest regions of space
We know both parts joined with AND must be parallel, X is a subordinate clause introduced with that
In Y too, we need some suitable uses that makes this part another subordinate clause, and the gerund persisting is doing exactly the same.
Out of the given options:
A. persisting : correct as discussed
B. persists : it cannt refer to particles, it should have been persist
C. persisted : This past formation is at least necessary, the another clause is in present, this formation not used to introduce clauses
D. they persist : they refers ambiguously to more than one antecedents: particles, astronomers, even in gmat terminologu atoms and particles are likely antecedents
E. are persisting : Note the uses of and, another verb is incorrect.