Answer:
Your answer would be that A, C, and D are punctuated correctly.
Explanation:
In all its versions, the sentence above contains a relative clause. Relative clauses contain a subject and a verb, they are introduced by a relative pronoun, and they function as adjectives. In this case, the relative clause is postmodifying the noun Adriana.
As Adriana is a proper noun, the relative clause above is nonessential because its information is not essential to identify the noun it modifies. That is why it should be offset from the sentence with proper punctuation. This could be by means of a pair of parentheses (a), the em dash (d), and commas (c). All these punctuation marks indicate that if the relative clause was removed, the meaning of the sentence would be left unchanged (1).
1) Adriana is studying painting in school
Answer:
A{ Adriana (who won a prestigious art award last year) is studying painting in school.
C{ Adriana, who won a prestigious art award last year, is studying painting in school.
D{ Adriana—who won a prestigious art award last year—is studying painting in school.
Explanation:
