Final answer:
The underlined word in the excerpt is best defined as b. acts of protesting.
Step-by-step explanation:
The underlined word in the excerpt is best defined as acts of protesting.
In the context of the passage, the sentence discusses how the moral crisis cannot be resolved by repressive police action or increased demonstrations in the streets.
This suggests that the word refers to people taking action to express their disagreement or discontent. Therefore, the correct option is b. acts of protesting.