Please please help How was the H. L. Hunley used during the Civil War? *
A. It was a Confederate ship used by Robert Smalls to gain his freedom.
B. It was a Union submarine to help strengthen the blockade.
C. It was General Sherman's secret weapon used to impose total war.
D. It was a submarine used to attempt to break the Union blockade.

it is D

Explanation:

Hunley, byname Hunley, Confederate submarine that operated (1863–64) during the American Civil War and was the first submarine to sink (1864) an enemy ship, the Union vessel Housatonic. The Hunley in a water tank at the Warren Lasch Conservation Center, North Charleston, South Carolina.

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