Gresham Sykes and David Matza termed this technique B. denial of injury.
A is incorrect because they are not appealing to the higher loyalties, they are simply denying something. They are also not denying their responsibility, because they obviously stole the car. They are also not condemning other people because they know the responsibility is theirs. Thus, B is the correct answer - they say they didn't hurt anyone - this is what they are denying.