The correct answer is A) the South's strong military tradition.
What gave the Confederacy an advantage over the Union during the Civil War was the South's strong military tradition.
It is well known that the Confederate Army had a stronger military tradition that the Northern Army. Many of its leaders had a great experience on the battlefield such as their participation in the Mexican-America War.
Although the Confederated Army had more experience, the Union's Army was better equipped because more industries in the North produced weapons and war supplies.