Answer: He is arrested for simply going for a walk.
Step-by-step explanation:
A dystopian society is referred to as a society which imposes an oppressive, harmful, and miserable existence on the members, it's seen as a wrong and unideal society. A dystopia society is the opposite of the utopia society which is an ideal society.
Therefore, the story elements most clearly suggest Mead is living in a dystopian society in "The Pedestrian" is when he is arrested for simply going for a walk.
Therefore, the correct option is B.