vestigial structures are considered evidence because scientists believe they are structures that were once used by a species ancestors but are not longer needed. these structures do not impair the organism in any way, so there is no need for evolution to get rid of them. for example, the human appendix is considered a vestigial structure.
I would say B because thermal energy is created from the engine and other parts of the car and mechanical because the car that was stopped had potential energy but moved when hit with the Jordan's car, creating mechanical energy. hope this helps