I believe the answer is A, but am not 100% sure.
The main reason why the border states did not secede in 1860-1862 was because they were concerned with the large amount of military coercion that was taking place in the South, and they felt that the South was ultimately unjustified in removing itself from the Union.
Answer:
It greatly weakened Lee's army?
Explanation:
The first battle the confederacy lost was bull run, the union didn't win the war at the battle of Gettysburg so I think that's the best choice
