How are a series and parallel car different?

I'm guessing the concepts of series and parallel are being applied to the methods used to provide the propulsion power for the vehicle, but you should check the definitions given by whatever source is asking the question. I don't know anyone who uses such terminology. I can only base my answer on the general meanings of the words "series" and "parallel" and my knowledge of circuit theory where series and parallel elements are common concepts. From the multiple choices given, I therefore select the last one, with a high degree of confidence (100% actually), as the correct answer:

"A parallel car has both an electric and gasoline engine."

Series and Parallel are different methods of electrical wiring and distribution. It has NOTHING to do with whether a car uses gasoline or not.

They are ALL BAD CHOICES so NONE OF THEM.