I know it's late, but it's Eve.
America's 16th President was Abraham Lincoln. Lincoln was elected in 1860 and served until he was assassinated by John Wilkes Booth in 1865.
Lincoln is famous for his leadership during the Civil War, his eloquent speeches, and the signing of the Emancipation Proclamation. He is largely considered one of America's greatest leaders along with George Washington and Franklin Roosevelt.
Answer: William Henry Seward wanted to add to the amount of land that the United States owned.
I think it is C I hope this helps -T