Answer: Memmott explains that the tragedy is not well known today and then shows why it is worth remembering.
Explanation: In the passage A, we can see a brief introduction to the subject by informing about a commemoration called "Border of Lights" in Dominican Republic, and it also explains that this commemoration is about a tragedy that was forgotten for a long time, and that many people don't know about. To complement the first paragraph, passage B describes what was the tragedy that occurred in Dominican Republic, where many Haitian were killed just for being Haitians, in this way he emphasizes in why this tragedy needs to be remember.
These excerpts work together to develop a central idea because Memmott explains that the tragedy is not well known today and then shows why it is worth remembering.
Explanation:
Passage A talks about the objective if the celebration.
Passage B tells the story of the cruel ways of Trujillo to kill Haitians and why they should be remembered.