Roughly 27 percent of the mass that _________ the universe is actually dark matter, rather than observable atomic matter.
9
writingWhich choice completes the text so that it conforms to the conventions of Standard English?
A
makes up
B
are made up by
C
are composing
D
made up
Correct Answer: A
Choice A is the best answer. The subject is "mass" (singular, non-count). The verb "makes up" agrees in number and is in the simple present tense, appropriate for a scientific fact.