Thanks for the question! So we’re being asked here for the main point of the passage. Throughout the passage, it’s describing the corrido and telling us what it is in detail, and also looking at how it is important to Border communities. So the main point is likely going to have something to do with this.
Now take a look at (E), which tells us that the main point of the passage is that the corrido is a type of folk song that promotes cohesiveness in Border communities through the use of familiar conventions. And we can find this right at the end of the first paragraph: sure, corridor commemorated significant local happenings, but more importantly, they served to affirm the cohesiveness of Border communities through their heavy reliance on familiar linguistic and thematic conventions.
Hope this helps! Feel free to ask any other questions that you might have.
