Final answer:
In the sentence provided, "a vintage Karmann Ghia" is an appositive phrase that explains "My father's favorite car", which is option B). The appositive provides more information about the noun it follows.
Step-by-step explanation:
The appositive phrase in the sentence is "a vintage Karmann Ghia". An appositive is a noun, noun phrase, or series of nouns placed next to another word or phrase to identify or rename it. The purpose of an appositive is to provide more information about the word or phrase it follows. In the sentence given, the appositive is providing more information about "My father's favorite car". Therefore, it is option B) favorite car that is explained by the appositive phrase.