Answer:
b. The rise of the Tammany Hall political machine.
Explanation:
The rise of the Tammany Hall political machine was the best demonstration of the power of Irish immigrants in New York. This organization helped to empower thousands of New Yorkers, mainly Irish Catholic immigrants, in the late 1800s.
I believe the answer is: Retrieval cue
Retrieval cue refers to a type of stimuli that help you to retrieve a certain form of memory.
For example, when you're often being abused with a belt when you're a child. Seeing a belt as an adult might serve as a retrieval cue that bring back the bad abusive memory.