Option 1 -> "Distant" means far away in space or time, not brief or temporary.
Option 2 -> "Softened" means made less harsh or intense, unrelated to duration.
Option 3 -> "Fleeting" means lasting for a very short time, which is synonymous with momentary.
Option 4 -> "Marked" means characterized by or noticeable, not related to time duration.
Hence, Option 3: Fleeting -> The word appears in the passage as "she felt a fleeting connection to home," indicating a brief, momentary feeling that doesn't last long -> correct