based on the quote, what is Lincoln’s primary goal?

“ if I could save the union without any slave, I would do it; and if I could do it by train all the slaves, I would do it; if I could do it by free and leaving others alone, I would also do that.”
- Abraham Lincoln, August 22, 1862

a. Freeing the slaves.
b. Not addressing slavery.
c. Punishing the south.
d. Preserving the union.

d. Preserving the union.