Which choice completes the text so that it conforms to the conventions of Standard English?
A
Smith:
B
Smith—
C
Smith
D
Smith,
Explanation
Correct answer: C.
Choice C is the best answer. The convention being tested is punctuation use between a subject and a verb. No punctuation is needed when, as in this case, a subject ("Her portrait of novelist Zadie Smith") is immediately followed by a main verb ("is displayed").
Why the other choices are wrong
Choice A
Choice A is incorrect because no punctuation is needed between the subject and the verb.
Choice B
Choice B is incorrect because no punctuation is needed between the subject and the verb.
Choice D
Choice D is incorrect because no punctuation is needed between the subject and the verb.