Final answer:
The most significant line in Susan Glaspell's play "Trifles" related to justice is D) "Somebody slipped a rope round his neck and strangled him and you didn't wake up?" It highlights the injustice and neglect of domestic violence.
Step-by-step explanation:
The most significant line in the development of themes related to justice in Susan Glaspell's play "Trifles" is: "*Somebody slipped a rope round his neck and strangled him and you didn't wake up?*"
This line emphasizes the injustice and the lack of attention given to the abuse and mistreatment that Minnie Foster, the suspected murderer, experienced in her marriage.
It raises questions about the responsibility of society in recognizing and addressing domestic violence. The line suggests that justice is not only about finding the culprit but also about acknowledging the injustices endured by others.