Andrew Johnson Had Been Put on Lincoln's Ticket as Vice

Andrew Johnson had been put on Lincoln's ticket as vice president in his second term  

A) because Lincoln's first vice president, Hannibal Hamlin, had displayed southern sympathies.
B) to appeal to War Democrats and pro-Union southerners.
C) as a safe choice in case Lincoln died in office.
D) as a poor white who balanced Lincoln's aristocratic background.
E) to appeal to Union soldiers and radical Republicans.