The correct answer is A. The star of many film comedies.
Step-by-step explanation
According to the explanation, an appositive or appositive phrase is placed after a pronoun or a noun to explain it in greater depth. This resource serves to deepen an explanation. For example, in the sentence "Groucho Marx, the star of many film comedies, also had his own television show" the pronoun is "Groucho Marx" and the appositive phrase "the star of many film comedies" because it expands the information on the character you are referring to with the pronoun. According to the above, the correct answer is A.