The right answer is A. by sending unarmed supply ships to the fort.
In his inaugural speech, Abraham Lincoln was explicitly defending that secession was unconstitutional but was not willing to invade the South. But in this attempt to resupply the Fort Sumter in the south resulted at the beginning of the war. When South Carolinians shucked Fort Sumter, in Charleston Harbor, Lincoln began his call to arms. Other southern states seceded at that point, and the Civil War was initiated.
