The answer to your question would be that the type of clause that is italicized in the sentence is the following one: Adjective clause.
Explanation:
The subordinate clause above is an adjective clause, also called relative clause. This clause is also an essential relative clause because the information it provides is necessary to complete the meaning of the sentence and to identify the noun it modifies. Therefore, it can't be removed for it would altered the meaning of the sentence (see a).
This relative clause is introduced by the possessive relative pronoun <em>whose</em> and it modifies the noun <em>look. </em>
