If you cannot find the answer to this in your text/study materials, then read, read, read here:
https://www.google.com/search?q=Koryo+culture+korea&oq=Koryo+culture+korea&aqs=chrome..69i57j69i60.5838j0j7&sourceid=chrome&ie=UTF-8
what change did the Koryo culture make to who could become an official in Korea's Government?
2 answers
this was.... NO HELP AT ALL