The main cause is poverty and lack of education. They're very poor, so they can't afford school. If the children do go to school, they drop out very young to work and help earn money for the family. That's not the kind of cycle people can break out of easily.
Add to that the civil war from 1960 to 1996 where the military persecuted the native people, killing up to 200,000, and they've had a pretty rough time of it.
In the poem "Garden of My Childhood, the author’s childhood garden is a metaphor for his home country, China. With great sorrow, Chang has to leave the garden of his childhood, that is to say, China, and flee to another country (America). Therefore, the central team of the poem is exile, and Chang’s feelings about leaving his home and his new life.
The last option, because it was formed when the courrupt bargin happened.
The answer is D. Thank you