Why did the goals of the Republican Party change during the Civil War

The Republican Party, often called the GOP (short for “Grand Old Party”) is one of two major political parties in the United States. Founded in 1854 as a coalition opposing the extension of slavery into Western territories, the Republican Party fought to protect the rights of African Americans after the Civil War.

Explanation:

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