The sentence that most contributes to the theme of hysteria is:
b. "Is the accuser always holy now? Were they born this morning as clean as God’s fingers? Vengeance is walking in Salem."
This statement captures the essence of hysteria as it highlights the moral panic and suspicion that pervades the community, suggesting that the accusers may not be as virtuous as they claim and that personal vendettas are driving the accusations—key elements in the theme of hysteria.