The Emancipation Proclamation took effect.. A. immediately after President Lincoln wrote it.

B. before the battles of Chancellorsville and Antietam.

C. many years after the end of the Civil War.

D. after Southern states refused to rejoin the Union.

Option D.

D.after Southern states refused to rejoin the Union.

Explanation:

Emancipation proclamation was issued by President Abraham Lincoln on January 1, 1863. The proclamation states that all all people held in slavery should be set free. President Abraham Lincoln has always opposed slavery which made him to issue emancipation proclamation. It was issued during the third year of United States civil war. It was decrease that freed slaves could be enlisted in the Union's army which in turn will increase Union's available manpower. It was done for the rebellious state to rejoin the union.

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