What was the result of the confederate attack on fort sumter, south carolina on april 12, 1861

The Union blockade, is the correct answer.

Explanation:

In the Civil War of America, Abraham Lincoln, the then U.S. President inducted a naval tactic, recognized as the Union blockade. This approach was exercised to obstruct the Confederacy from trading. The principal purpose for exercising this plan was the challenge, the Confederacy produced to Lincoln by bequeathing the union regarding it a power of the state, and striking Ft. Sumter on April 12, 1861.