Answer:
C. To emphasize that the US was founded on the principle of freedom for all people.
Step-by-step explanation:
The Gettysburg address was an address that the President Lincoln gave to the public at Gettysburg Pennsylvania and it is the most famous address by the presiden Lincoln, he speaks about the principles on which the United States were founded, firmly believing on equality and freedom for all people, this was crucial because the fight agaisnt slavery was at its peak.