What are the challenges of trying to study a culture with a lost language?

Studying a culture with a lost language means you don't know the culture behind it so it makes it harder to study.

Explanation:

The loss of language undermines a people's sense of identity and belonging, which uproots the entire community in the end. Yes, they may become incorporated into the dominant language and culture that has subsumed them, but they have lost their heritage along the way.Language, he believes, is not inherently linked to culture. ... of fewer languages is not only less work, in terms of learning and maintenance, ... present; tribal roots and unified national identity is one many nations struggle with.

if i am correct the answer is going to be a) the federal program of reconstruction ended.