For Question 17, the meaning of "borrow" that most closely matches its meaning in the passage is:
c - verb | take as a loan
In this context, "borrow" refers to the act of taking something (the "souvenirs") for a temporary period, albeit unauthorized.
For Question 18, the flashback found in Paragraphs 14-17 in "Catch the Moon" is:
c - Hearing the funeral parlor’s name, Luis remembered, too.
This indicates that the mention of the funeral parlor triggered memories for Luis.
For Question 19, the flashback reveals what about Luis:
d - using anger to mask his grief at his mother’s death.
This suggests that Luis's emotional response is tied to unresolved grief relating to his mother's passing.