Answer:
It become harder for them to learn about their cultures/ancestry
Explanation:
The reservations is a set of land that the US Government provided for Native Americans as a form of compensation because they forcefully taken the native's land in the past.
Since The reservation was designed by the government, many of the objects that exist in reservations mimics what exist in white culture. For example, rather than living in a hut, most of them lived in houses that we commonly see in cities.
In the past, Native American children learn about their cultures through the teaching given by the adults. Over the years, many Native Americans choose to leave the reservations in order to seek job opportunities. This make the younger Native Americans generation have very few sources to learn about their ancestry.