The composition of the rocks recovered from the meteor's impact site ______ unlike anything previously documented on Earth.
Which choice completes the text so that it conforms to the conventions of Standard English?
- A
were
- B
have been
- C
are
- Dcheck_circle
is
Explanation
The subject is "composition" (singular), not "rocks." The intervening prepositional and relative phrases do not affect agreement. Singular "is" is correct.