The subordinate clause<em> who played the part of Prospero</em> can be identified as an B. adjective clause.
Explanation:
A <u>subordinate clause</u> is a clause that is dependent on a main clause and is usually introduced by either a conjunction or a relative pronoun. <u>Adjective clauses</u> in particular are dependent clauses that function as adjectives because they describe a noun or pronoun.
<u>Adjective clauses</u> can be <em>essential</em> (they provide essential information to describe the noun or pronoun) or <em>non-essential</em> (they provide extra information that is not necessary to understand the ultimate meaning of the sentence.) <em>Non-essential adjective clauses</em> are set off with commas, such as in the sentence<em> </em><em>Bryan, </em><em><u>who played the part of Prospero</u></em><em>, was the star of the play The Tempest.
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