...and the "which" is misleading.

"My car which is old" turns out to the be the right answer in terms of getting it correct for the quiz, but I think this is the wrong translation in English of the phrase, "Ma voiture ancienne". The right translation would be "my old car" or possibly "my ancient car". This is ambiguous in English, as people say "my old car" and it can mean either "my former car" or "my aged car" depending on context. Also, when I had the question presented to me in a 10-question quiz three times (and it was not in a short quiz), it had only two answers, which is unusual for a long quiz. The list of single-select options in the long quizzes usually have three items.