I got the same answer as you so try picking the answer that is closest to the answer you got sorry i couldn't help much
Mentality /Outlook / viewpoint. Here are a few synonyms - they all fit into the space and does not change the original meaning of the sentence.
Answer:
I think how much did your last car cost is the best question
Explanation:
because by asking that you can know how did that person buy that car and where did they get the money to afford it
