Which of the following is correct regarding the following quote by abraham lincoln: "if i could save the union without freeing any slave, i would do it; and if i could save it by freeing all the slaves, i would do it; and if i could do it by freeing some and leaving others alone, i would also do that."

a. lincoln's primary purpose in the civil war was to grant freedom to slaves.
b. lincoln's primary purpose in the war was to allow for equal rights for all african americans.
c. lincoln was mostly concerned with preserving the union of the united states.
d. lincoln was an abolitionist.