Option 3. Adriana, who won a prestigious art award last year, is studying painting in school.
Explanation:
Clause is an expression which consists of subject and predicate irrespective of grammar and sentence.
There are two types of clauses:
Restrictive clauses, Nonrestrictive clauses.
Restrictive clauses gives information which gives meaning to the sentence.
Nonrestrictive clauses gives additional information which in particular is not necessary for the sentence.
Coming to the question as it should be punctuated in nonrestrictive clause the answer is
Adriana, who won a prestigious art award last year, is studying painting in school.
