Answer: their
Explanation: The sentence is addressing car buyers having something, in this instance a choice. When the subject is possessive, you use their. Such as, the car buyers ate <em>their</em> lunch.
"To write a novel", is the subject in the infinitive phrase.
His ultimate goal is to write a novel. So, "To write a novel" functions as a noun in the sentence. Hence, the answer is A. Noun.
Answer: White clothing is a symbol of shame.
Explanation: I did the test and got it right:)