Final answer:
Wadsworth's action of slamming the door indicates that he dismisses the Motorist which corresponds to option (b).
Step-by-step explanation:
From the provided scene description in which Wadsworth slams the door in the Motorist's face, it can be inferred that Wadsworth's action is dismissive in nature rather than welcoming or confrontational. The act of slamming a door generally indicates a strong desire to shut someone or something out in a forceful and abrupt manner, which corresponds with option (b) Wadsworth dismisses the Motorist.