The subject complement in the sentence: ‘My face is cold’ is letter c: cold. Subject complements are any noun, adjective, pronoun that proceeds after a linking or helping verb (am, is, are, was, were, has been, are being, might have been, etc.], be, become, and seem. They are also called true linking verbs. In the sentence, the linking verb is ‘is’ therefore, the subject complement out of the given choices here is ‘cold’ (functions as adjective) towards the subject ‘My face’.